Groupon offers a Custom Message Delivered on a Large Potato from Anonymous Potato for $6.50 plus $4.20 for shipping. (After purchasing the voucher from Groupon, you'll be able to customize your potato at Anonymous Potato.) That's a $7 savings and the best deal we could find for any custom potato service. Anonymous Potato anonymously delivers a potato with a custom message (up to 140 characters) to the address of your choice. The voucher is valid for 90 days from purchase date.