One of favourite "fix it on the fly" gags was a software upgrade that had gone through testing and proved to be a pile of poo in live. Many weeks of tweaking later all was sorted and the go-ahead for further rollout was given.
The developers had provided a nice, self-extracting, install, migrate and configure package that tidied up after itself. Trouble was, its only real run in anger had been the original "pile of poo" installation and much tweaking of its contents had occurred since.
The result was something where you pressed a button, it shat all over the environment and then removed all traces of itself (leaving only the thoroughly stuffed remains of the system) so you couldn't see what had gone wrong. Oh how we laughed......