All others that come to mind are centralized -- Liberty Reserve, Pecunix, e-gold, etc. They're not very crypto, either. Well, e-gold tried, but went down hard.
Then there's the Global Settlement Foundation, which has a much broader agenda, and Loom, which is basically a truly humongous spreadsheet. There could be interesting synergies, IMHO.
I want to add the concept craighto mentioned. LETS. Local exchange trading system.
Bitcoins differs from LETS in several ways but it is similar in other important ways. One very important similarity is both currencies are virtual and created/backed only by the shared participation of a voluntary, self selected, community.
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This is from wikipedia but I think people will see the parallels with bitcoin.
"A number of people have problems adjusting to the different ways of operating using a LETSystem. A conventional national currency is generally hard to earn but easy to spend. To date LETSystems are comparatively easy to earn but harder to spend. The success of a LETSystem is therefore determined by the ease with which a person can spend their LETS credits, and improve their quality of life by participation. Placing difficult arrangements or unreasonable service fees in the way of LETS members will produce difficulties in the future."