A few uses that So Creative Things suggest are;
Using them to make your home-made jams look extra special. Simple place your case onto the lid and then tie with a bit of ribbon or cord. You could personalise the cases you use depending upon the recipient of the gift. Using the Blue or Pink Gingham cases for the new mum. Or perhaps using the Red Snowflake cases for that extra special chutney for all the leftover turkey at Christmas.
Another great idea is to use them to make matching wreaths for your party.
The Complete Guide To Imperfect Homemaking has a really detailed tutorial on how to make them, I think these would look great at a Baby Shower or you could even make Halloween ones using the Black Cases and the Orange Ghost ones!
For all those who love to make Cake Pops Veronika posted these sweet little Baby with Bonnet Cake Pops on Bakerella. You could use the Gingham (Blue or Pink) cases or you could use the Yellow Spot cases for those who are not revealing the gender.
I think you make your cake pop and then slide your case over the stick, you could fold it at the bottom if you find it a little big. Then tie a cute little ribbon in a bow and draw on your face.
One final great idea is if you are finding that there are no cases to match your colour scheme is to make dip dyed ones. Little Wren has a brilliant tutorial to do this. They use White Cupcake Cases and Food colourings and according to their comments the dye does not transfer onto the cakes when baking. They suggest to leave them to dry for a while, however it would be perfect to fit in with your party/event colour scheme.