My ISP (Telenet in Belgium) may just be unusually good, but, while there's fairly sparse documentation on IPv6 and their DHCPv6 only gave me a /64 by default, a

My ISP (Telenet in Belgium) may just be unusually good, but, while there's fairly sparse documentation on IPv6 and their DHCPv6 only gave me a /64 by default, all I needed to do to get more was to configure my router's DHCP client to request a larger delegation. I didn't need to even contact their support line. At the moment I'm only asking for a /60, because that's all I need, but I strongly suspect that a /56 or even larger is easily available.