I was also thinking about a coin with an automated air drop (the preliminary success of
Auroracoin seems to indicate that Airdrops are actually a good thing).

Each wallet that at a given time has X coins in it, will receive a 3*X air drop. Creates instant interest
in mining (and possibly buying) some coins to get several wallets with the given minimum.

Repeat this cycle every 3 months, upping the next minimum coin requirement to X' = 5 X.
This leaves a 1*X coin gap per wallet until the next air drop, requiring more mining (or buying)
to keep up.

It's kind of a proof of stake system with a continued motivation for mining or buying.
Note that the airdrops are NOT filled from pre-mine, but rather as PoS transactions.

Some inflation is built in, however it should not be a problem if the number of users of the coin
grows at about the same rate.

Christian