CPU Speed Accelerator
CPU Speed Accelerator allows you to drastically increase the CPU allocated to your foreground applications to make the most of the power of your Macintosh.
CPU Speed Menu
(commercial) CPU Speed Menu allows you to switch between the different performance settings of your computer by a single mouse click.
Maintenance is a System Maintenance and Cleaning utility. It allows you to run misc tasks of system maintenance: repair permissions, run periodic scripts, reset Spotlight's Index, rebuild the LaunchServices database, delete Application, Font and System cache, check the status of the Hard disk.
Tactor tries to guess the best action for current text selection. For example consider text containing http://xyz.com ? an URL link. Or ~/Documents/MyPresentation.key ? a presentation file. Both matchers and actions are fully customizable.