I used to be the only guitarist in my band, and always enjoyed trying to keep a full and balanced EQ with only a single guitarist and probably the worst bassist you've ever heard in your life. Whenever I play with another guitarist I don't care much for a normal lead role so much as almost a harmony role. I especially like it with riff driven music.
Stuff kind of like Amon Amarth. As much as I hate the band and song, the strange riffs in "Are you dead yet?" by Children of Bodom is a perfect example of absolutely amazing harmonies at work in the oddest places. Slayer does a lot of it, too. I'm not much for that type of metal since high school, though. I normally listen to Jazz/metal fusion type stuff that does this a lot too. Cynic does it in pretty much every song and solo in such delicate ways that it can be really hard to pick up on. I could go on about bands and how they really change the idea of a "lead" guitar, but I'm sure you get the idea. I preferred being more of a layer than an actual "I play solos" type of guitarist.