I recently tried a trial period of the app CleanMyMac for Mac OS X. After uninstall I see that its still left its folder actions in my finder context menus.
How can I remove them?
You may want to check your Library folders. The files that cause the appearance of the folder actions can be found here:
Uninstalling software can be a pain sometimes, but applications such as Appzapper do their job pretty well. You can find it here macupdate: appzapper
CleanMyMac leaves more trash than that. Search for "CleanMyMac" in your ~/Library folder, and delete all that shows up.