Uhmm...that's a rather broad open ended question, but the generic answer is (as you already stated) anything is possible. The keys to working a strange role, or a different take on a role/religion/cabal/etc are as follows:

1) Know your limitations, don't try to play a Lich paladin if you don't think you're up for the challenge.
2) Patience, patience, patience...if you're playing a role that's off the norm and requires immteraction(tm) don't hang it all and give up 100 hours into your character.
3) This fits in with 2, but stick to your role at all times, you never know who may be watching. Roleplay, roleplay, roleplay.
4) Take advantage of every opportunity you get, within your role. If you're playing a bard who wants to record the history of Thera and a tale telling contest pops up...you'd be a fool not to be there. However if your character is playing an xenophobic drow assassin...it probably wouldn't be a place your character frequented often.
5) perhaps the most important...use common sense. Hopefully I don't need to tack any explanation onto this one.

Anyway, hope this helps

Thanks for the tips, they are greatly appreciated.