Leopard Trouble
I received an email from an EasyCrop user this morning saying that dragging to the Desktop no longer works. I ran some tests and found that I was able to drag to Finder windows but not to the Desktop. This seemed like a Finder bug to me, so I restarted the Finder (Cmd-Opt-ESC and select Finder, then click Relaunch) and, sure enough, dragging to the Desktop started working again.
On a related topic, I have also seen Leopard (Tiger too, but this seems to be happening more since I upgraded) get into a state where Dashboard and Exposé stopped working. Restarting the Dock process fixes this. To restart the Dock, enter the following command in the Terminal:
killall Dock
If you’re not comfortable with Terminal, you can also force quit Dock using Activity Monitor.