I recently played a show with The Nashville Celts at the Middle Tennessee Highland Games and we came up with a bunch of new music for the show, among which was a tune that I wrote called Grand Street. Since this was the first time I'd ever written anything that I didn't immediately hate it was also the first time I'd ever performed anything that I'd written live, so I managed to get a video of it and posted it to my YouTube channel. Check it out if you're so inclined.
This is a tune that I play with The Celts as well at sessions as it's a very popular tune. I learned it from the famous Irish band The Bothy Band (along with everyone else, probably!). It's a 4-part reel in A minor and it's a great one to pick up because it's likely to pop up at sessions just about anywhere you go. Since it's so common, be sure and listen to other folks playing it (particularly the Bothys) as it's always good to hear what other people can do with the same melody.