Exactly what the title says. Not "in the future it could be" or anything like that, I mean what *is* canon right now/over the series' history?
Certainly one-sided ships count, so "Brock/every girl he's seen" is a big one, even though only one of them really bothered to return it and he wasn't even aware of that (Lucy, although...have there been others?).
For instance, do you consider Mars/Cyrus canon, or do you consider her attachment to him just part of her obsessive devotion? Does it vary from canon to canon? How about something like Rocketshipping, which is absolutely canon in Electric Tale but only played around with on the show? And so on.