Dave sez, "Cafepods do a wide range of coffee pods, including ones which they claim to be compatible with the notoriously DRM'ed Senseo (click on "Coffee pods" in the top bar, then page 2, and "Dark Roast double pods NEW!" and details). I've been buying their double espresso pods for my Gaggia machine for a while, and they're pretty good – individually foil wrapped."
(Thanks, Dave!)
Update: Erik Olson sez, "I don't think describing the Senseo pods as DRM'ed hardware is fair. There's nothing stopping you from using whatever pods you want — I know of at least three vendors selling them, and the only sensor in the pod compartment is the 'compartment closed' sensor — a good safety to have, given the temps and pressures involved.
"The Senseo now is how inkjet printers used to be — you could buy the manufacturer's cartridges, third party carts, or even refill them. There are reusable filter pods for the Senso that let you use your own coffee — the coffee maker doesn't stop you from using any of them.
"DRM, in hardware, is best shown by current inkjet printers, where there's hardware that keeps you from refilling the carts or buying third party cartridges. The only punishment for not using Senseo pods is the possibility of a high-pressure coffee shower."
