Hmm, lots of good ones, but lets start with one that is funny now, but sure as hell wasn't at the time....
So my regular band gets a show on the local stop of the Vans Warp Tour. We get the gig through a local producer who has label connections as an instrumentalist and just released a cover getting airplay in England. He needs a backing band for his song and likes enough of our stuff that he learns the vocals for 4 of our tunes and we're going to do a 5 song showcase...Sounds like fun and if things go well we get to open for a national act I love a week later at a top venue.
Where to begin...
1. My drummer gets the jitters and hits the Jack D at 8:00 am and passes out the FIRST time by 11:00 am.

2. Our stage breaks down on the way from the previous show and is running late. We get our slot rescheduled for later in the afternoon.
3. My drummer wakes up and keeps drinking hiding Jack in Pepsi bottles so we can't take it away.

4. Confusion with craft services means we're not getting chow, so we're on our own eating $15 burgers and $5 waters....for 12 hours in 95 degrees with no real shade.
5. Drummer passes out again in the truck.
6. Traffic starts to pick up in the area, and one of my friends coming to the show calls my cell and says he passed our stage about 20 minutes ago broken down about 10 miles away.
7. Drummer wakes up and notices his shoes are off. He begins looking for the "lousy bastard who stole his shoes" - which are laying in the footwell of the truck he passed out in....

8. Our stage arrives and we get rescheduled at a time slot opposite a national act on the other side of the grounds killing our crowd
9. We finally get on stage. Backline looks decent. Stage appears sturdy. Wooden floors have lots of holes though.....Hmmm
10. Just before the first song, my "armored" instrument cable gets wedged in between floorboards in a narrow gap. It leaves me stuck in a 12" diameter circle to play - Directly behind my singer (6'4" 340lb - I'm 5'7.....).

11. We get a count off from the drummer and WHAM - he plays the wrong song part. Yep. My singer turns around and we make panicked eye contact - we have 20 minutes of this S^^T
12. I have no monitors and can't reach the front of the stage because of my cable.
13. The band now realizes the guy who got us the gig, who is singing our stuff, but isn't our singer, is not a front man at heart. Pure pucker factor. No stage presence, barely audible vocals....

14. My regular singer steps up and starts doing the performance like it should be except the FOH guy has him buried in the mix (I heard later)
15. Bass backline suddenly goes intermittent in song 2. (we're the last band on the stage tonight and I'm guessing somebody didn't check something) but I can't tell if it's FOH or just the backline (it was FOH also)
16. Drummer almost falls out of his throne off the back of the stage at the beginning of Song 3.
17. After we get off stage my buddy comes up to me and says "nice job" with the same look as someone is caught F&^%ing your wife and you walk in on him.....
But I still think the Goat story wins (Goats can F&^K you up!!)
Not the worst, just one slice of a middle aged bass players gig life....