Here's the latest version of graphDS. In this version, I added nesting for catalog functions, added tracing for inverse functions, added a vector data type, and added some catalog functions for working with vectors, like dot product and cross product. If you've never used graphDS before, it also features expression evaluation, a simple CAS, built-in catalog functions, and six graphing modes. Please note that this will probably be the last version before the "final" version, 1.0. This means that I NEED YOUR HELP. Please report any bugs (I already know of several) and tell me what features you would like to see implemented or how I can improve graphDS. I cannot guarantee that I will be able to include all your suggestions, but it would certainly help both you and me if I could get some feedback. As always, I greatly appreciate your donations. Your donations will keep me from having to obtain a job while I am getting through college, which means more homebrew for you. Click here to download graphDS v0.9.