These 4 coupon codes worked for me at GoDaddy just a few minutes ago.
Rocket99 - 1 new or transfer .com for 99 cents + ICANN Fee
prag295 - 1 new or transfer .com for $2.95 + ICANN Fee
geekbox - 1 new or transfer .com for $2.95 + ICANN Fee
junecomf - 3 new .com registrations for $4 each + ICANN Fee
Rocket99 - 1 new or transfer .com for 99 cents + ICANN Fee
prag295 - 1 new or transfer .com for $2.95 + ICANN Fee
geekbox - 1 new or transfer .com for $2.95 + ICANN Fee
junecomf - 3 new .com registrations for $4 each + ICANN Fee