I started this summer out with a big wish list of games to beat. I originally went with a "summer theme", meaning tropical or ocean in aesthetic. I managed to beat all these before I burned out:
Everblue 2 (PS2)
Greendog The Beached Surfer Dude! (Genesis)
Submarine Attack (Master System)
Deep Blue (TG16)
Dive: The Medes Island Secret (Wii)
Battle Shark (Arcade)
ThunderJaws (Arcade)
The Little Mermaid (NES)
The only other "ocean" themed game I plan to beat this summer is Aquanaut's Holiday: Hidden Memories on PS3. But I'm still waiting on my copy to arrive from Japan.