By no means do I think she did it better than Joplin. But Pink's AOL Sessions performance of Me and Bobby McGee has stuck in my head for decades now. (And for what it's worth, both are better than the original from Kristofferson)
Second choice, and another one that I legitimately think is better than the original, *Tweeter and the Monkey Man" by The Headstones.
Edited: Honourable Mention, because no one ever actually tops The Clash. But Captain Tractor did a version of London Calling that is one of my favourites.
Edited: Okay...one last one. Specifically for the Saskies. Captain Tractor's version of the Arrogant Worm's "Last Saskatchewan Pirate".
For a bit of context, back in the 90s, my then girlfriend and I were decent friends with the band. Enough so that whenever they would come to Saskatoon they'd crash at our place and we'd go hang out backstage at their shows. Weird because the reason we knew them in the first place was because the drummer was my girlfriends ex....but hey...it was the 90s.
Just an all around bar-band all about drinking songs. Something young people don't do anymore. Was talking to a buddy of mine the other day about how every bar we used to go to in the 90s has been demolished.