Micro 4/3 lens adapters:
Panasonic 4/3, DMW MA-1  

Panasonic DMW MA-1 4/3 to Micro 4/3 adapter. Purchased on eBay.

Pros: Electrical couplings for automatic aperture and autofocus. Good quality front and rear bayonets.

Cons: Expensive. Plastic body may flex with heavy lenses. Autofocus with most current Micro 4/3 cameras is essentially unusable with 4/3 lenses.

A newer version of this adapter is available. It is, as far as I can see, essentially identical to the first version except for small cosmetic changes.