Out of pretty much nowhere we got an e-mail about an updated version of the super old Mac level editor Hellmaker:
The awesomely wonderful Mac Doom editor Hellmaker hasn't been updated since 1997, and as a result it lacks support for the new flags used by sourceports. Through the wonders of ResEdit, I've updated the program to add support for all BOOM/Legacy linedef tags, thing types, and sector specials. The updated program is available here for the enjoyment of the one or two Mac Doomers still around.
So yeah, if you use a Mac and have always wanted to edit for Boom (hello and welcome to 1998) then here is your chance. There's no webpage up, but you can download it here (751k).