iDisplay app turns your iPad or iPhone into secondary screen – too good to be true?

How cool is this? iDisplay is an app that tricks your computer into thinking you’ve got a secondary display attached, and then pushes what would be on that display onto your iPad or iPhone. That’s… brilliant.

I mean, I can think of about a billion uses for this. As many uses as I have uses for my actual computer, in fact. The problem is that there’s some latency, as it sends the display information over wi-fi, so you can’t watch video or play games on it, or really anything that requires precision timing or responsiveness. Unfortunate, but that may improve with time.

Costs $5. It’s only for OS X right now, but there’s a Windows version in development.

[via TUAW]