Dai-Gurren-Lagann

Think about it. 1) Both of the main characters are known as Diggers. 2) Both main characters always wear blue. 3) Both main characters constantly have to fight giant robots. 4) And in the end, both main characters have to face off against an enemy (Megaman Juno and Anti-Spiral) who plans on destroying all lifeforms due to the population exceeding a certain limit (this ironically happens in both stories when a baby is born (there's a side quest in MML where you have to find a pregnant woman out in the forest and get her to the hospital because she went into labor)). Kinda makes you wonder a crossover between the two would be like.  Volnut