A quick tip for TrueCrypt users that I just figured out for myself: if you don't want your volumes to be unmounted when you quit the TrueCrypt GUI application, go to the Preferences screen and uncheck "TrueCrypt quits" under "Dismount all volumes when".

Previous versions of TrueCrypt never used to unmount volumes unless you explicitly told it to. I can't remember which version changed this default behaviour, but it used to really irritate me! I suppose it's another case of erring on the side of security rather than convenience, the classic polar opposites.