Multiple burner capability using at least two burners is found in the following programs:
Padus DiscJuggler, Nero, CDMate, VOB Instant CD/DVD, CDRWin beta, Feurio Pro (primarily audio)
Prassi/Veritas PrimoCD Plus / Sony CD Extreme / Stomp Click 'n Burn / PSXCopy 2000 / Veritas My CD Pro / Stomp RecordNow Max. These are all the same basic program created by Prassi Europe (purchased and owned by Veritas). In my experience, the Prassi clones are among the most efficient in resource usage and fast burning times for dual burning.
Some, like the Prassi clones will run burners from different sources, i.e., entirely separate recording jobs can be run simultaneously with one instance of the program running. Obviously, this puts an extra strain on resources compared to multiple burning from the same source. However, the miracle of buffer underrun protection technology can make this possible even with IDE burners.