Er, guys, this is not a reactionless drive. This is just a reaction drive where you can leave the engine home to work on it. Charles Sheffield and Robert Forward have both written about variants of this drive; Forward even proposed a variant on this drive (combining it with a solar sail) so you could even use it to *stop* at your destination. I'll look up the actual info when I get home to my library for exact quotes.
Sorry 'bout dat.
Sorry 'bout dat.