I Do:

Nice, fat, long series which go slow and in-depth.

Ranma, Neon Genesis, Sailormoon (bleah), Ah! Megami-sama, and many more - though they may be just inspirational material.

 

I Don't Do:

Lemons - and if you think I'm talking about a sour, citrous fruit, then forget the whole idea entirely.

One-shots. At the moment I don't have anything simple enough to put into a single short story.

Spamfics. Just on principle.