I just finished cave diving in a code base that's had a very old ticket to clean up the mess.
I went in with 3 tickets in mind to fix. I found half a dozen more while I was down there, and created 2 myself. I don't know if I got off easy or I was distracted and missed things.
The other project I'm working on is not dissimilar. Hey did you guys know you have a massive memory leak?