Probably means that you played and completed it some time ago, and the state is still in your browser's Local Storage. (Mine was too)

The atoms in my brain must have been recycled into paperclips

It means a lot of paperclips (about 20% the mass of the observable universe by my calculations, assuming 1 gram per paperclip and using Wikipedia's definition of 1.5e53 kg for the observable universe).

It's thankfully not a huge spoiler, the title alone practically gives it away. It's all the twists on the way there that is really enjoyable to uncover, in my opinion.

I'm new to this game and I have no idea what this means - so I guess I avoided the spoiler...