So, who else here likes to buy pre-painted DDM minis and then mod the hell out of them? 
Mods that I have done/am doing:
Mind Flayer Scourge (Dungeons of Dread): My first, very minor, modding project was when I got a group of these guys and couldn't stand the pink tips on their tentacles. (Are they supposed to be wearing some kind of tentacle-sleevies or something? Underdark camo paint?) So I painted the tentacle tips to match the rest. I'm now thinking about painting them all mauve, that being the traditional mind flayer skin tone.
Green Slaad (Blood War): After reading Monte Cook's "Modifying Slaadi" article, I was inspired to do the same thing with mine. I did things a little differently from Monte; I painted the nodules black instead of blue, and I painted over the eyes entirely, then added new eyes lower down on the face - bright yellow ovals with no pupils. The result looks a bit like a Teenage Mutant Ninja Turtle gone horribly wrong, but TMNT beats Kermit the Frog any day...
Grick (Dungeons of Dread): I got a bunch of these because I wanted a cheap, all-purpose tentacle monster. However, I hadn't realized when I ordered them just how silly the bright blue color scheme would look. I painted them to match the old Giants of Legend grick minis (green backs, yellow bellies, white-rimmed suckers), and bought one of the old ones to serve as an alpha. I used a high-gloss sealer to make them look wet and slimy, and am quite happy with the results.
Sand Giant (War Drums): I'm trying to put together a good set of giants - hill giants, fire giants, and frost giants. Unfortunately, all the fire giant minis I could find were $9 and up, and I didn't really want to shell out that much. So instead, I bought six sand giants and am turning them into fire giants. I used green stuff to sculpt great long manes of hair and huge beards, then snipped the ends off the truncheons in their left hands and attached hammer heads instead. Next I'm going to paint them with black skin, red-orange hair, and soot-blackened steel armor. So far they're looking good. Certainly my most ambitious modding project to date.
Mezzoloth (Blood War): I got a bunch of these and found that their tridents were ridiculously floppy, bending all over the place. I got some thin steel wire and used it to wrap the tridents in, which stiffened them nicely, but was rather obvious even when painted... so I covered up the wire with a thin layer of green stuff. The tridents look okay now, but they're stupidly thick. In retrospect, I should have just used green stuff from the start and not bothered with wire.
Rimefire Griffon (Legendary Evils): This one is next on my list once I finish up the sand/fire giants. A set of rimefire griffons was perfect for my griffon needs, good-looking minis for less than $2 each... except they were stark white! Well, thought I, no reason they had to stay that way. I'll be painting the back halves a tawny color and the front halves in brown, with yellow talons. I intend to leave the heads white, so they'll resemble bald eagles.
Female Human Barbarian (PHB Heroes Series 2): I always wanted a frenzied berserker, but wasn't willing to pay eight bucks for it. Yesterday I discovered that the PHH series has a repaint of the same sculpt, available for much less. The only drawback is that the repaint has her cloak in the same bright blue that made the gricks look so silly. So, I ordered one and plan on repainting her (re-repainting? un-repainting?) along the lines of the original.
What sort of DDM-modding projects have you done? How did they turn out?

Mods that I have done/am doing:
Mind Flayer Scourge (Dungeons of Dread): My first, very minor, modding project was when I got a group of these guys and couldn't stand the pink tips on their tentacles. (Are they supposed to be wearing some kind of tentacle-sleevies or something? Underdark camo paint?) So I painted the tentacle tips to match the rest. I'm now thinking about painting them all mauve, that being the traditional mind flayer skin tone.
Green Slaad (Blood War): After reading Monte Cook's "Modifying Slaadi" article, I was inspired to do the same thing with mine. I did things a little differently from Monte; I painted the nodules black instead of blue, and I painted over the eyes entirely, then added new eyes lower down on the face - bright yellow ovals with no pupils. The result looks a bit like a Teenage Mutant Ninja Turtle gone horribly wrong, but TMNT beats Kermit the Frog any day...
Grick (Dungeons of Dread): I got a bunch of these because I wanted a cheap, all-purpose tentacle monster. However, I hadn't realized when I ordered them just how silly the bright blue color scheme would look. I painted them to match the old Giants of Legend grick minis (green backs, yellow bellies, white-rimmed suckers), and bought one of the old ones to serve as an alpha. I used a high-gloss sealer to make them look wet and slimy, and am quite happy with the results.
Sand Giant (War Drums): I'm trying to put together a good set of giants - hill giants, fire giants, and frost giants. Unfortunately, all the fire giant minis I could find were $9 and up, and I didn't really want to shell out that much. So instead, I bought six sand giants and am turning them into fire giants. I used green stuff to sculpt great long manes of hair and huge beards, then snipped the ends off the truncheons in their left hands and attached hammer heads instead. Next I'm going to paint them with black skin, red-orange hair, and soot-blackened steel armor. So far they're looking good. Certainly my most ambitious modding project to date.
Mezzoloth (Blood War): I got a bunch of these and found that their tridents were ridiculously floppy, bending all over the place. I got some thin steel wire and used it to wrap the tridents in, which stiffened them nicely, but was rather obvious even when painted... so I covered up the wire with a thin layer of green stuff. The tridents look okay now, but they're stupidly thick. In retrospect, I should have just used green stuff from the start and not bothered with wire.
Rimefire Griffon (Legendary Evils): This one is next on my list once I finish up the sand/fire giants. A set of rimefire griffons was perfect for my griffon needs, good-looking minis for less than $2 each... except they were stark white! Well, thought I, no reason they had to stay that way. I'll be painting the back halves a tawny color and the front halves in brown, with yellow talons. I intend to leave the heads white, so they'll resemble bald eagles.
Female Human Barbarian (PHB Heroes Series 2): I always wanted a frenzied berserker, but wasn't willing to pay eight bucks for it. Yesterday I discovered that the PHH series has a repaint of the same sculpt, available for much less. The only drawback is that the repaint has her cloak in the same bright blue that made the gricks look so silly. So, I ordered one and plan on repainting her (re-repainting? un-repainting?) along the lines of the original.
What sort of DDM-modding projects have you done? How did they turn out?