David, I'm from Otaku Software, the developers of TopDesk. Thanks for mentioning us :).
If you'd like to drop me a line via my email address I'd be happy to send you a beta of the next version of TopDesk - it includes a new way to switch windows that's not a feature of any OS that's out *yet* (hint, hint ;)).
Hi Shane, I'm from Otaku Software. Great to hear that you find TopDesk useful. I'd just like to point out that the trial isn't time-limited, so it won't run out and disappear by itself. Maybe it's accidently been uninstalled? If it has, you can grab the trial again from our website, reinstall it, and use it as long as you'd like.