Hi - I'm a composer. Players looking for a short, fun showpiece for the bass might be interested in trying my Microncerto, which was commissioned to be played by Dominic Seldis with the BBC National Orchestra of Wales. Since its premiere, it has also been performed by Lenny Finkelshteyn with the North Carolina Symphony, and in performances with the BBC Concert Orchestra and BBC Scottish Symphony Orchestra. You can view the full score at SibeliusMusic, where you can also print it out for free (and hear a MIDI version); a recording of Dominic's performance can be downloaded, again at no cost, at this site, and I can provide a version for DB and piano (for rehearsal or performance purposes) on demand. The piece was originally commissioned to display the full range (in every sense) of the bass to young people, but since then it seems to have been taken up for general public concerts too.