Martian Slingshot: CPU hungry!
I tried Martian Slingshot to synchronize 2 folders between my desktop hackintosh and my MacBook Pro, I began with my main shared folder, my 160GB+ picture folder and subfolders. Seems to work flawlessly, even if interface was not as cute as I expected.

But I quickly discovered that SlingShot launch repetitively gnutar (each minute with synchronization from my MacBook Pro), with a good amount of memory and a real CPU-hog, using 100% of one core (mono-threaded tool! again!) on my computers for long time, and slowing them down with many hard-drive access (temporary files).
Sorry, but I expect a synchronization tool to work flawlessly, to be able to work under the skin (launched in background), that SlingShot doesn’t enable, and moreover, I expect it to be respectful of my computer resources while I use it, to let me do MY work instead monopolizing more than 50% of the resources of my Core2 Duo laptop!
So SlingShot, that is a commercial application is really not for me. I will continue to look for a simple application, elegant, fast, running in background, to synchronize my work between my Mac OS X computers at home…