TextPad for editing my HTML files (and CSS for that matter)
PaintShop Pro for my graphics needs (and pilotbob, I do have Paint.NET too, but I like PSP better)
mobidedrm.exe for my DRM'd books (I just can't stand typo's and must fix them!)
mobi2oeb to create HTML files from my mobi books
ereader2html.exe to create HTML files from my ereader books (I have 1! atm, thanks to that overdrive debacle at FictionWise
)
Info-ZIP to create an epub book
epubcheck-1.0.3.jar to check my epub book
mobigen to create the final mobi book
I made a batch file to 1. create an epub book, 2. check the epub, 3. repeat steps 1 and 2, until the HTML is correct, and 4 create the mobi book.