Advise.
If you live in Tokyo for more than a month, you have probably learned the shuffle/waddle you use to navigate the crowds. It's amazing how this wears me out. If you come to Akihabara, and want to enjoy the atmosphere, by all means come here on a weekend and waddle around. If you want to shop for video games, manga, computer parts, anything electronic basically, I was here on a Monday at about 11:00 am and it was cheez-whiz.
I have little interest in games, but the used books and little stores that are tucked away are fun. Definitely worth a visit. Here's a pic of nothing that you would associate with Akihabara.