Seeed Studio is getting into the Halloween spirit, they are giving away blinking buttons to any purchaser from 8th to 17th of October. They are also rewarding first 50 Halloween themed pictures to be posted on their flickr account with a pirate head wrist strap.
There is also a Halloween contest:
This is a competition to see who can build the best and coolest Halloween-related stuff. Basically, you can build anything Halloween-related (e.g. costumes, pumpkins, monster masks whatever) that is enhanced with electronics in whatever way you think fit.
Via contact form.