Assigning a /32 to subscribers.

With public IPv4 becoming quite scarce now, I have an impetus to save addressing wherever possible.

I'm already assigning /31s to customers, but I figure if I could assign /32, I could double the number of subs for my given addressing.

I'm thinking that this would be achieved by assigning /32 to the client via DHCP with a gateway not on the same subnet, then proxy-arping or thereabouts for the gateway address.

Does anyone do this currently? I've considered PPP, but for resource reasons I prefer not to use it.