Macworld has posted an article by Albert Filice explaining how to create your own Fusion Drive from a normal hard drive and an SSD. It’s not difficult if you’re comfortable working in Terminal, but be sure you have full backups before you start, because the process will erase both drives. follow link
Untrash the Trash
Feeling trasher's remorse? On Snow Leopard, you can open the Trash (click the Trash icon in the Dock) and "untrash" individual items there. Select one or more trashed items (files and folders) and choose File > Put Back. This returns the items to where they were when you originally put them in the trash. The keyboard shortcut is Command-Delete - the same as the shortcut for trashing an item in the first place, since in deleting something from the trash you are untrashing it.
Make Your Own Fusion Drive