I set one up over a decade ago because Verizon said that they would need 6 months to deploy IPv6 on FiOS. I'm still using it.
Unfortunately in the meantime spammers have discovered HE tunnels and now I get a lot more CAPCHA's than I used to. I still check my FiOS link every month to see if Verizon has turned it on yet.
https://www.tunnelbroker.net/