Possible to run scripts on sleep and wake? MacBook Pro 2010 running OS X Lion.

Is it possible to run scripts on sleep and wake events?

My specific application is that I've got Dropbox-synced Truecrypt volumes that  I regularly use on both my MacBook and iMac. I rarely shut down my MBP since closing the lid is much faster and easier, but this means that I have to remember to dismount my Truecrypt volumes and let them sync back up before closing my MBP. It's trivial enough to script mounting/dismounting of them, but I'd like to go a step further and have these scripts run automatically.
SleepWatcher may be of use. 

From the description: It can be used to execute a Unix command when the Mac or the display of the Mac goes to sleep mode or wakes up, after a given time without user interaction or when the user resumes activity after a break or when the power supply of a Mac notebook is attached or detached. It also can send the Mac to sleep mode or retrieve the time since last user activity. 

It's working fine for me on 10.6.8. Various versions are available to support 10.1(!) thru 10.7