Crossover Madness

Prince of Tennis + BLEACH + Ouran Koukou Host Club. Pretty comprehensive for Prince of Tennis, anime-only for Ouran, and anime and manga for BLEACH through, uh... the beginning of the Arrankar arc or so. Generates any cross-fandom combination (meaning you might wind up with two from the same fandom, or two from any permutation of the three).

Random fact: Ueda Yuuji was in all three of these anime series.