This is good
news. We have several touchscreen-enabled Macs at my day job, all from Troll
Touch. Earlier this week they announced that the 20" Intel iMac will be added to their lineup. Their system
uses the Mac's existing screen, so there's nothing you need to attach to the front (that kids constantly pull off,
prompting frequent recalibration). Like I said, I support several of these, and we've never had a problem. You can make
use of the display with either a stylus or a finger.
You can order a touch-enabled 17- or 20-inch iMac Core Duo directly from Troll Touch for $2,275US or $2,675US respectively, or they'll convert the one you already own for $869US and $1045US (including round trip shipping).