I'm all Dean Markley when I can get 'em, D'Addario if I can't (even when I was getting D'Addarios for free). My hands don't sweat when I play, so as long as nobody else touches my guitars the strings easily last for years. My VSH-445 still has the strings I got it with, and that's easily 4-5 years ago now. Quite a few of my guitars were last strung when I lived in NYC in 2006.
Mostly standard 10s, some light top/heavy bottom (Tele, LP Jr.), some 11s (Kalamazoo KG-2A, LP Jr., sometimes on semi-hollows). Basses also Markley or D'Addario, different gauges & styles for different basses.
The Westone Villain currently has 9s on it (Boomers), but they're going away soon & I'll see how the Kahler Spyder is with 10s.
eyebulger's VSH-455 got D'Addario 10s with a wound G when it was here, I liked that set a lot.
12-string electric uses D'Addarios. Baritone uses Danelectro strings.
Acoustics always get John Pearse strings, unless I'm given something else to try...and then I go back to Pearse again:
www.jpstrings.com/je