It works nicely and, of course, its free. But it only activates the screensaver that you've got set in System Preferences. And, as yet, there's no menubar activation.
For a more sophisticated way to go(and for $10), there's "xBack". It allows you to select ANY of your screensavers, and configure them as well(provided the screensaver itself has that option), right from your menu bar. Or, as with Wallsaver, activate it from your Dock.
But Wallsaver is just a pup. Who knows what features the developer will incorporate into it over time. It might very well give xBack a run for its money one day. Stay tuned.
(I'm a hard-core screensaver junkie....just love interesting, unique ones. Got over 40 of them in my collection, so far.)