Alternatives to MLCad (Mike's LEGO CAD)?

[Stryker295]

Yo! I've been using MLCad for years to digitally construct robots—either because I didn't have my LEGOs with me, or because I wanted a digital copy of something I'd already made.

I know there's a few alternatives, including one from LEGO that is amazingly terrible, but there's at least one or two GOOD ones out there, that have all the LEGO parts. Can anyone remind me what those are called?