I'm a real do-it-yourselfer; I DRP (dividend re-invest) with optional cash purchases directly from the company through a transfer agent. I have three stocks with three transfer agents. I put a set amount in each each month, more if I see the self-addressed stamped envelope handy. I treat this like a tennis game; when the ball is in my court I hit it back.
No broker, fees are paid by the company, and I invest in decimal amounts too. I can also "flip the switch" in my old age and with a check box on my deposit slip I can get my dividend check. While my DRPs are officially free, it means that those fees are considered income and are taxed. But we are talking a couple of bucks here. Two of my DRPs even send me SASEs, so I don't even pay for the stamp.
Why? I'm patient, and while I write relatively tiny checks each month (dollar cost averaging), it means that all my bucks go to buying stock. You've got to be patient - setting some of these DRPs up takes months.
I like the idea of Sharebuilder, however I currently set aside such small amounts that the $4 trade fee is a bite of what I set aside per month. Still might look into it when I can invest more and if I want to invest in companies whose formal DRP isn't a deal.