I just dead-headed mine and can't bring myself to throw out good seed. :) Open to swap offers (mostly flowers or herbs that I'm looking for at the moment) or happy to send without a swap, it's only the cost of a 2nd Class stamp. :)
I've never been wild about grape hyacinth, as it does look scruffy when it goes over - BUT the bees love it, and it was the first thing in my garden this year to give them pollen. So if you have space, a good early bee plant to bung in somewhere.
I don't know if it will flower the first year from seed - happy to send a few bulblets as well, if anyone is keen.
cheers,
H