It's $35/month for the service, from San Francisco's coolest indie ISP (founded by Rudy Rucker's son, Rudy Jr, it was the inspiration for Pigspleen, the fictional ISP in my novel Little Brother) and if you opt to pay a little extra, they'll install a free link in a low/medium income neighborhood, too.
Setting up a link is pricey — $2500 — but for $100 you can sponsor a free, open wifi access point to one of the other links, establishing pockets of free, anonymous, open Internet access across the city. Depending on your location, you'll get 350Mbps to 1Gbps throughput!
I don't live in San Francisco anymore, but I just funded an open access point.
This project will have several impacts. Most obvious is that you will get a high end link to your home. Less obvious will be the strengthening of our core network and the ability to have more high speed fail-over pathways. Also, we'll be able to service more areas of SF and boost capacity in already served neighborhoods. There is also the altruistic aspect of donating double a link cost — we will deploy in an area with lower medium incomes and grow our networks in those areas: helping us grow helps bridge the digital divide and fosters a San Francisco based company.