Jamawkinaw Enterprises has released Downcast 1.0.11, which adds an option to switch to audio-only playback of video podcasts. Selecting this option in the video context menu closes the video but continues playing the audio. The podcatcher app also squashes a bug that caused file extensions to be dropped for imported episodes, fixes priority play for playlists, ensures that statistics for partially played episodes are properly refreshed, fixes a problem that prevented the selected podcast/playlist from being reselected after a restart, and fixes multiple bugs that could cause crashes. ($9.99 new from the Mac App Store, free update, 6.4 MB, release notes)
Single Time Machine Backups
Tired of Time Machine running all the time? You can turn it off in the Time Machine preference pane, but still initiate a single backup by choosing Back Up Now from Time Machine's menu bar icon. Of course, your backup is much less likely to be up to date, but Time Machine won't be taking any resources while you're trying to work.