I was never interested until I got into a roleplaying group for a while, and they'd order pizza for the all-nighters, including sometimes a Hawaiian (the guy whose house it was at grew up in Honolulu). It's really tasty! Like a dessert pizza.

One chain around here does a variation on a Hawaiian that they call a "Paia Pie", which also adds mandarin oranges. I was dubious but it works.