I'm bringing this back from the dead because I'm in the process of building my own Frankenstein setup and have been debating on what to do for a 2.1 amp setup. I actually have an older 35wpc (6 channels in all) BSG amplifier w/preamp controller that is bridgeable. Only issue is disabling the unusable internal xover network so it can run full range and let the speakers' passives do the work.
Other than that, I'm seeing limited options since I don't have the time right now to build an amp(kit)...One of the easiest solutions I see is to simply find a cheap stereo receiver and add a suitable plate amp from Parts Express for the Tangband 740c 8" sub I've had laying around. Other option is to use a small Dayton or Sonic T amp but they're only good for about 5-10wpc realistically, plus the Sonic is $70 plus shipping ($45 for the Dayton) and I could probably Ebay a good receiver for the same price or cheaper w/lots of headroom.
Any other 2.1 plate options other than the underpowered Keiga 25x2/50w sub plate option from Madisound and the UK company posted earlier?