Here's my "comprehensive list":
LePouLe456: ENGL Powerball Simulation, with all channels and modes.
HyBrit:A two channel amp. One channel is a Marshall Plexi 100 Super Lead and the other is a Marshall JCM 800.
SoloC Head:One of my favorites, it simulates a Soldano SLO 100 Head with all it's channels and modes.
LeCTO:Simulates the two dirty channels of a 3-channel Mesa Boogie Dual Rectifier.
LeXTACAlso, one of my favorites, it simulates a Bogner Ecstasy head.
LeCab 2:Since none of these amps come with speaker simulation, LePou makes a free plugin you can use to load your own cabinet impulses (more on that below).
Variety of SoundFerricTDS: Tape saturation and dynamics.
NastyDLA: Tape delay and chorus.
DownloadE-phonicRetro Delay:Variable tape delay simulator. One of the few that can generate 'sound on sound delay' without regeneration. Here's a example(using LePou LeXTAC and LeCab as amp):
0ther ones
Camel Audio Alchemy Player: Free version of Camel's excellent Alchemy Soft Synth. Also comes with it's own presets and a libary.
Yellow Tools Independence Free: Free version of Yello Tools' Independence Player. Comes with 2 Gb worth of sounds.
Well, I could add many more plugins in here. But I could remember only these.