So yeah, wow, I just finished Giant Robo. This has to be one of the most amazing things I have ever seen, and considering my frequent indulging in Miyazaki works, that is saying alot.
It's about 7 episodes long, with each episode spanning anywhere from 40 minutes to an hour, but damn does it fill alot into that time frame. It's about a fictional world of the future, where something called Shizuma Drives have replaced all other forms of energy, being cheap, compact, versatile, reusable, and completely non-polluting, there is literally nothing that doesn't use a shizuma drive.
The story focuses on the IPO (Internation Police Organization), with it's elite squad of "Experts of Justice" as they fight against the secret organization "Big Fire" and it's own elite squad, the Magnificent Ten, who's ultimate objective is world domination. Also, in this world of the future, all the most competent people in the world possess super powers for some never explained reason, as well as giant robots, which include the titular robot, Giant Robo, IPO's strongest weapon.
I don't want to spoil anything beyond that, but trust me that this is an amazing anime, brilliantly made, full of incredible characters in amazing situations being completely awesome. I'm going to have to assert Giant Robo as an anime essential that everyone should watch.
It actually took me years to find this one, and I'm surprised it hasn't garnered more popularity than it has.
Also, as both a note and an ironic twist, the non-canonical side-series, Ginrei Gaiden, is surprisingly lame, being one-shot silly stories involving the characters from Giant Robo.