2 egg whites = an egg, so you can use them in any other recipe calling for eggs. I also like the freezing idea.

I think it's an opportunity to make an Angel Pie. It's a meringue pie shell filled with chocolate and topped with whipped cream. The best recipe I've seen is in Lora Brody's Growing Up on the Chocolate Diet.

I freeze them until I have enough for a brown sugar or lemon angel food cake.

you can also freeze them

Forgotten Cookies! Easy, keep for ages, and fun. Drbabs has a good recipe on food52; mine uses a bit less sugar and no nuts. Peppermints smashed are good in it too!

Meringue... Make shells for filling... They will keep in a large tupperwaRe container for a long time.

Egg white omelet or your can freeze for later use.

macarons!

Meringue shells for filling w/fruit or pavlova. Egg whites freeze really well; just remember to mark how many there are on the container, though.

Egg white omelet for my always dieting friends. Meringue cookies. I made a spinach casserole with leftover egg whites that's posted at the site, too.

You can use one to bind a rice crust for a quiche - lapadia has a great, easy recipe on food52.