Setting up an older iMac as a secondary display

I've needed to upgrade my current iMac for some time now, and with the new models shipping next month, I think that time has finally come.

I'm currently "using" (most of the time I just sit there and stare at it while it attempts to complete the simplest of tasks - I can barely run iTunes and Photoshop at the same time) the old 6,1 24" Core 2 Duo (the last of the white models). Since it's probably not worth my time to sell it, I was thinking I could salvage it and use it as a secondary display for my new machine.

Most of the research I've done has indicated that this isn't as simple as it sounds, although it seems as though Screen Recycler may be a good solution.

Has anyone used Screen Recycler or know of a more effective alternative to setting up an older iMac as a secondary display?