I have a stealthy-as-hell Rogue|Warlock hybrid multiclassed into Assassin that I'd love to see played out to epic. Combining Cunning Sneak with Shadow Walk allows him to make a Stealth check to hide anytime he moves 3 or more squares from where he started, and I've been adding encounter teleports to basically build him into Nightcrawler. By epic he should pretty much just be able to stay hidden all the time and bamf all over the place. I have a paragon path picked out for him, but not an epic destiny (yet).
I do have one epic character: a Swordmage|Warden hybrid multiclassed into Wizard that is a very sticky defender. Having enemies work hard to get away from me (including by teleporting) and just being able to say "get over here!" is pretty fun. Definitely a classic tank. The Wizard multiclass is only to support his cold theme, which isn't an essential element of the build -- but it's pretty fun to pull a bunch of guys over with Ensnaring Bolts and then drop a Blast of Cold on all of them.
The other two characters in that party, which is currently running through Tomb of Horrors 4E, are:
- A classic Twin Strike eladrin archer Ranger with a vicious longbow and a war ring -- at 23rd level she's rolling 6d12 crit dice and crits on 19-20. If you like rolling a lot of dice, that could be a good route.
- A dragonborn Warlord who has put half his feats into dragon breath. He can drop flaming acid on everyone's heads 3-5 times in any given battle. From above, because he can fly.
Finally, in terms of straight up dishing out punishment, I played a greataxe-wielding warforged battlerager Fighter who would have been an unstoppable engine of devastation had that game made it to epic. I wanted to play a big robot with a big axe, and it didn't disappoint even in heroic tier. I have a paragon build of him kicking around as a contingency.
If any of those are interesting, I can post more details.