A lot of classic shmups also happen to work as metaphors for insemination. The last level of R-Type Final immediately comes to mind. Wouldn't you know it, but there is a guy who's taken that theme even further, with the game like Space Phallus and the award-winning Scoregasm.
For some mysterious reason, Scoregasm is 75% off just for today. The game has plenty of interesting bullet patterns and interesting mechanics to explore, so if you like that kind of thing, you'll like this thing. Rumor has it that if the game sells 1,000 copies during this sale, it will be available for free tomorrow. If you buy it today, you could be paying it forward for your poor internet brothers and sisters in the future.
What would Haley Joel do? I think he'd have a Scoregasm.