Sunfire TGA-7400
I am new to Sunfire (and high(ish)-end audio for the matter) and got a great deal from an installer with a unit that didn't fit someone's system.
I run it with the new Onkyo PR-SC885 Pro (awesome unit) and Salk SongTowers and SongCenter. I'll be adding 4 in-wall surrounds soon.
I like that the TGA-7400 has balanced XLR outputs, runs COOL, is very powerful, and sounds incredible. For fun, I hooked it up as Carver suggests trying: biwiring the front speakers so that current-outs run the bass and voltage-outs run the highs. Since I haven't played with other hook ups, I can't say if it makes an audible difference over other hook-ups.
Now if only it could be smaller, lighter, and cost less.