What FREE D&D software do you use?

[Angel Tarragon]

A friend of mine bought me E-Tools for my birthday last year.

 

[Astalanya]

I love Tiera Star's XP calculator; it was a scramble when Arcady0's site disappeared to find another.

Everything else I don't use with any frequency. SpellGen is a new addition, and Monster 3.5. I'm still seeking a statblock outputter.

 

[ElvishBard]

Interactive Dungeon (just google it) is free and while it doesn't do everything, it is free, easy, and you can move the PCs around the map as they go through it if you choose. It is the best one I have found, and I use it for almost every dungeon/castle/interior thing (including caves) that I need.