For my 25th Season of (ideas for) my Spin off site, www.maggieanderic.com , I came up with this idea:
25.20: "Bob" (season Finale) Sideshow Bob's existance, besides dropping by to give Bart a hassle every once-in-a-while, has taken a 180 degree turn--now the hunter has become the hunted as Cecil is 'promoted' to the head of the Springfiel mafia and Cecil's first bit of business is to end his sibling rivalry by getting rid of the Sibling. Knowing in private that something like this was about to happen, Bob waits for Cecil to make his move. The next morning, Bart and Jessica are kidnapped by Cecil and threatens to kill Bart and Jessica, thus stopping Bob from having his revenge. However, Bob doesn't want to get back at Bart anymore and wants to be able to say he got even with Cecil, again. So, in a action-esque manner, Bob goes into the mafia compound to get Bart and Jessica out.
I even did a picture based on this idea, here:
http://www.nohomers.net/staff/jake/bob3.jpg
Jake