Things like reddit gold, a one months subscription to netflix, or a vpn.
Netflix prepaid cards if such a thing exists.
Physical 3d printed cheap coins, so rather than paying an extra couple hundred dollars for a gold coin with a bitcoin code I can pay 11 Peercoins for a Plastic 10 Peercoin coin.
By the way
www.reddit.com/r/ppcmarket just opened up and would love it if you posted whatever you're selling there too.