wingsandsword
Legend
I love Unearthed Arcana, it's become my great DM's toolkit of useful and neat stuff. I'm using a lot of its variants in my current campaign.
Reducing Level Adjustments (working well, because those +x ECL races/templates are a lot weaker at high levels)
Bloodlines (working well, personally I prefer them to templates for adding "something special" to PC's)
Racial Paragon Classes (also working well, lets PC's focus on their character's racial heritage and makes humans even more flexible).
Specialist Wizard Variants (one variant Enchanter PC, working well since it's some small changes that are balanced and fit with the character concept).
Character Traits (I like these a lot, more balanced than a flaws system, but adds some more depth to characters that's supported by good rules).
Defense Bonus (I liked it in Star Wars, d20 Modern and Wheel of Time, and it fits just fine in with D&D too).
Armor as Damage Reduction (I like the concept, the only downside is having to adjudicate changes to stock NPC/Monster stats on the fly. PC's really like it because those few points of DR do a lot for a PC's perception of power and safety, even if they only rarely save you.)
Action Points (learned to love them in d20 Modern, the more powerful D&D points work just fine in a high powered, cinematic game).
Metamagic Components (not been used much, there for flavor and if PC's want to sink money into it, but it's not come up besides just talking about it in-game and debating to invest in them).
Incantations (great for plot rituals, and also good for explaining why dungeons have the monsters they do, or how NPC's can perform effects that seem way over their level, and a scroll for performing an Incantation is a nice way to give PC's access to a spell needed for plot without waiting for the game to be higher level.)
Reputation (class based, another one I learned in Star Wars & d20 Modern and it's been okay. Not stellar, but it is a nice yardstick of how notable the PC's are, and how likely it is that the PC's have heard of a given NPC)
Reducing Level Adjustments (working well, because those +x ECL races/templates are a lot weaker at high levels)
Bloodlines (working well, personally I prefer them to templates for adding "something special" to PC's)
Racial Paragon Classes (also working well, lets PC's focus on their character's racial heritage and makes humans even more flexible).
Specialist Wizard Variants (one variant Enchanter PC, working well since it's some small changes that are balanced and fit with the character concept).
Character Traits (I like these a lot, more balanced than a flaws system, but adds some more depth to characters that's supported by good rules).
Defense Bonus (I liked it in Star Wars, d20 Modern and Wheel of Time, and it fits just fine in with D&D too).
Armor as Damage Reduction (I like the concept, the only downside is having to adjudicate changes to stock NPC/Monster stats on the fly. PC's really like it because those few points of DR do a lot for a PC's perception of power and safety, even if they only rarely save you.)
Action Points (learned to love them in d20 Modern, the more powerful D&D points work just fine in a high powered, cinematic game).
Metamagic Components (not been used much, there for flavor and if PC's want to sink money into it, but it's not come up besides just talking about it in-game and debating to invest in them).
Incantations (great for plot rituals, and also good for explaining why dungeons have the monsters they do, or how NPC's can perform effects that seem way over their level, and a scroll for performing an Incantation is a nice way to give PC's access to a spell needed for plot without waiting for the game to be higher level.)
Reputation (class based, another one I learned in Star Wars & d20 Modern and it's been okay. Not stellar, but it is a nice yardstick of how notable the PC's are, and how likely it is that the PC's have heard of a given NPC)