Another crossover that should not be is Peanuts/logical analysis. My newspaper is currently rerunning a series of old Peanuts comics from right before Hank Aaron broke Babe Ruth's career homerun record. That'd put it at either the end of the '73 season or the beginning of the '74 season. According to the strips, Snoopy is also apparently one homerun away from breaking the record. Snoopy plays little league games, which would probably amount to one game a week for a few weeks each summer. In order to have that many homeruns, Snoopy and the rest of the cast would presumably have to be trapped in some sort of 'eternal now' situation, able to rack up homeruns for decades without growing any older.
“I really hope I’m behind this convoluted mess; at least that way I’ll be able to get revenge by doing this to myself. I won’t even have to feel bad because it’ll be all my fault.” - Harry Potter, The Master of Death by Ryuugi.