CompuExpert is offering the PC version of Oni for $24.90 if you order during their 48 Hour Madness sale. They also offer the Mac version of Oni for $32.90, however that is their normal price. You can also pick up Rune and Star Trek Armada for $19.90 each as well as Kingpin for $12.90 during the sale.

I ordered Oni from CompuExpert on Monday and received it on Tuesday. I paid for FedEx 2-day shipping, but it came in less then 24 hours. You also get a free game with every order, whether you use Mac or PC. I can't recommend this place enough.