As a clawhammer banjo player who plays a lot with "Celtic" players, I worked out a way of playing jigs, although some tunes are more accessible than others. It's hard to describe, but basically each 6/8 measure consists of two sets of triplets. You use your down-stroke ("I" = index, although some people use the second figure) for the first and third notes of the triplet, and fill in the middle note with whatever works -- hammer-on, pulloff or dropthumb. So the notation could be I-H-I I-P-I or whatever.

For a "single jig" (to use dance terminology), the middle of the triplet could be a rest instead of a note. It coud also be a 5th-string thumb note, to keep the rhythm going.

Then I bought an octave mandolin, and now I usually use it for jigs.

The first tune I worked out in this style was "The Rakes of Kildare"; others were "The Swallow's Tail", "The Blackthorn Stick", "The Two Penny Piece", "I Lost My Love" -- those are ones I can think of at the moment, without sitting down with the banjo.

It works with some tunes, and it's fun, but for many it's more trouble than it's worth, I figure. However, I'm in the midst of composing a jig on the banjo. Perhaps it'll work out interestingly for the fiddlers of this world.