I think the concept of Freicoin's demurrage is intriguing, they basically selfdestruct at a fixed percentage over time. Such a demurrage could be added to devcoin (or rather a follow up) and the generation of new coins balanced with the demurrage to keep the total number of coins steady in the long run.

Combined with devcoin's 90% model, this would allow a foundation to constantly hand out coins for work, because the generation would never cease, while making the coins valuable. To keep a certain amount of coins one would either have to work for them constantly or buy more of them... I'm not sure if this would work out over a long time span, but the current non-stop process is guaranteed to make devcoins worthless in the future.