I just got my weekly email with Onlive's latest special - if 45,000 people "like" their facebook page (they're at 42,235 and counting) by the end of Labor Day weekend, they will sell Batman, Arkham Asylum for 99 cents.
Onlive's FB page
I've been using Onlive for about 3 months now, and if you have a decent broadband connection I recommend checking it out. They're always running cool specials, the games are priced pretty competitively, and, well, the service just works.
I use the service on my computer, occasionally on my laptop, and mostly on their microconsole, which I got for $10 (shipping cost, basically) - the controller feels very similar to a 360 controller.
I can be up and playing any game in my Onlive library within a minute and a half of starting up the service.
Just an FYI, hope you CAGs agree this is a decent deal - Arkham Asylum for a buck is pretty hard for me to pass up.