Octopus Energy posted me a 321 A4 page electricity bill printed out on paper as a physical 5cm thick package (on their "Agile tariff" the rate changes every half hour, so there are 48 line items per day). I enquired as to why they'd done that?
Apparently they tried to email it first, but the 15 MB email exceeded my email server's size limit, so they posted a hard copy instead.