I'm playing Colosseum to get the 4 pinch berries that aren't available in Emerald. Since I only care about getting the berries in Emerald, I thought I'd just connect my Emerald cartridge to Colosseum, register my in-game team, and then use them to smash Mt. Battle a few times - that way, I didn't have to actually trade my Pokémon over from Emerald and then trade them back afterwards. It seemed to work well enough, as I got just under 15,000 Poké Coupons from one run of Mt. Battle. I went back and cleared Areas 1 and 2 again, then bought a Ganlon Berry using the Poké Coupons associated with my Emerald cartridge and sent it over to Emerald.
All good, except now I can't actually find the Ganlon Berry anywhere. It's not in my bag on Emerald or on Colosseum, there's no one upstairs in the Pokémon Center who has it, Norman doesn't have it, and I can't think of anywhere else it could be. The purchase definitely went through - it shows I have 100 Coupons when I connect my Emerald cartridge, down from 15,100 - so where's the berry gone?
EDIT: It turns out it got sent to my PC. In other news, I am an absolute tit.