AMP: Artists' Meeting Place and Resource Collective

Artist Pension Trust - Berlin
In this system, you'd "invest" by contributing your art - 20 pieces over 20 years - which will then be sold by the Artist Pension Trust. A portion of proceeds go to you, a portion to the Trust, and a portion to all participating artists, allowing a group pension fund to build. Potentially very useful, especially considering that many artists don't work a job where pension benefits would normally accrue.

http://www.artistpensiontrust.org/