Dweezil Zappa

One of my favorite non-Frank versions of "Peaches en Regalia" was on the Dixie Dregs live album "California Screamin'" which Dweezil guested on.  There are not too many bands than can take on the task of covering Frank's repertoire but the Dregs were certainly worthy.  Another favorite of mine is Gov't Mule's instrumental version of "Pygmy Twylyte" which appeared on the bonus disc of "Live w/ a little help from Our Friends"  (Gov't Mule has also covered "Trouble Every Day" a few times live)

Others?