I've been playing Lumosity for about 10 months now; the free version, which gives you three games a day versus the five for a paying account.
Takes about 15 minutes a day, but I have seen big improvements in my memory and attention to details.
I would heartily recommend it to everyone.
hmmmmmm I'm going to have to try this. I've seen the commercials for it and figured it was a scammy thing.