Apart from taking a lappy to a gig to record it, Minidisc is still the easiest and better sounding method. I have a Pioneer full size one that cost me an unbelievable £12 on eBay, it's so light and easy to transport, and sound is amazing. It is possible to get a full set on a disc and then easy to edit down to your liking.
I remember when Minidisc first showed it's face and it was the end of the DAT recorder which many used to record, and for backing track play at many gigs, DAT still sounds awesome, but Minidisc definitely has the edge.
I will still be keeping and using mine.