If your parents will go for useful gifts, any clothes you might need, weaning things, things like that.
For 'big' toys, a lot of people do like an activity cube or sit-in thing. If it's a jumping one, though, check what the advice is on how long they should use it – I think a lot of the jumping things are only supposed to be used for 10-15 minutes at a time a couple of times a day. A push-along walker (not a sit-in one, they're not safe) is another option – some come with blocks or activities on the front.
For smaller toys, stacking cups, sensory blocks or balls, lift-the-flap books, some music-making toys (various electronic options available, but also xylophone, drum, maracas), a little car/animal/whatever with wheels they can push along the floor once they start crawling. Stacking rings, shape sorters, hide-and-squeak eggs, and the galt (or similar) pop-up people are all also good, but would potentially get more use from 12-18 months, so might be worth saving for first birthday ideas (but depends on the child).