Oldest game with a special attack meter?

[Segata]

All I can think of is Punchout. Not counting RPGs with MP refills.

[Ack]

I know for fighting games, it's generally considered to be Teenage Mutant Ninja Turtles: Tournament Fighters, so after Punch-Out.

SHMUPS is a good genre to consider though. Any experts know of any earlier examples offhand?

[marurun]

Art of Fighting could be considered to have this, after a fashion. It's not exactly the same, but it effectively powered your regular special moves.

[prfsnl_gmr]

I know for fighting games, it's generally considered to be Teenage Mutant Ninja Turtles: Tournament Fighters, so after Punch-Out.

SHMUPS is a good genre to consider though. Any experts know of any earlier examples offhand?

I think the original Samurai Shodown, with its “rage gauge” edges out TMNT Tournament Fighters by just a few months!