A2SDGUI is a free application that allows you to do some of the more interesting and complex Darktremor Apps2SD functions without needing to install ADB to shell into your HTC EVO or type commands in a terminal emulator.
For those who may have run into problems after installing Darktremor Apps2SD, or those who just want to experiment and see if they can gain any performance boosts by moving the Dalvik or Cache about, A2SDGUI gives you buttons to press as opposed to having to command-line it.
There are also options for swapping, memory freeing, turning zipalign at boot on or off, toggling the Dalvik JIT, moving and rebuilding the cache, and seeing some information on how things are going (e.g., memory, free space, cache status).
Be careful and make a Nandroid backup before changing anything. Making DTA2SD scripts easier means you can potentially shoot yourself in the foot with a much-easier-to-hold cannon.