I am not sure how long this will last, but this is a very good deal still working as of September 2014.
You can get any .COM domain from GoDaddy for just $0.99, plus any additional .COMs for just C$9.99 a year!.
I’ve tested it by getting myself a new domain WiseAPI.com for only $0.99 and it works.
When you are about to check out, at the bottom you’ll see an option:
Click it and then enter following code: cjc1comuk
Like this and press Apply button.
Note: this can only be used once a day and 0.99 is only for the first year. But still, this is pretty unbeatable deal.