i'm not real picky. i like cherry,apple and pecan on everything. either seperate or a mix of 2 or even all 3. i usually save my hickory wood for direct grilling steaks.
I've only had the pleasure of cooking over apple, cherry, hickory and oak.
I like to use a combo of fruit and hickory with pork.
and a combo of fruit, hickory and oak with beef.
I use the mix because you can pile fruit wood on all day and not worry about things getting out of hand flavor-wise, and the oak and hickory are a bit more pronounced, so a bit fills in for the milder fruit. To make an analogy: in a rub I like to use lots of ancho for deep chile flavor and just a bit of new mex, chipotle, or cayenne to bring the heat. get my drift?
I totally forgot to add that I like to burn whole spices too. Jerk chicken is awesome when cooked over a foil packet of allspice berries and cinnamon bark.