Little Snitch 3.5.3
Objective Development has released Little Snitch 3.5.3 with a significant reduction in the CPU load used by the Little Snitch menu bar item. The network monitoring utility also improves compatibility with OS X 10.10.4 Yosemite, fixes a bug that could cause the menu bar item to get stuck in highlight mode, improves searching for denied connections in the Network Monitor, and fixes a problem that prevented editing of multiple rule selections. ($34.95 new, free update, 21.2 MB, release notes, 10.8+)
I have a love/hate relationship with Little Snitch. Frequent updates are good but each update requires extended babysitting after install to get to a point where a machine will run without constant approval of connections approved in prior versions. My media server Mac Mini is always on and each Snitch update requires too much work after each update.