what can you get for $50? (non-profit pledging)

I've got a zencart set up for a non-profit group. It's the kind of situation where you can donate X amount and get a shirt, or a bit more and get a mug, that kind of thing.

What we'd like to do is let people say how much they want to donate, and then let them pick from a range of gifts, possibly combining lesser-priced things.

For example, say the minimum dontation for a shirt is $50, and a mug is $70. We want them to be able to:
-- give 80 and get a $50 shirt;
-- give 150 and get a shirt and a mug

etc

Does that make sense? Is there a nice and easy way to do this in zencart?

thanks

I take it you want this to magically happen?

Or can't you just read the donation and send them their gifty? :cool:

Thanks for the reply. I might not have been clear on what I'm asking.

We've got products set up in the cart for the thank-you gifts, with prices set for the minimum donation necessary to get that gift.

What we'd like to let people do is give more than the minimum, and pick which gift(s) they can get for that much. So, if the shirt is minimum $50, they should be able to give $80 and say "I want the $50 shirt for my gift."

Another way this could work: a "give X extra dollars" box somewhere, so they can pick all the gifts they want at their normal price and then add some extra. So, they pick the $50 shirt and then say "also, $30 bucks for nothing."

Does that make sense?

thanks much