GAP has their fall sale (up to 60% off) while supplies last, also use coupon code FIFTY
for 50% off on top of that, and Shipping is Free on orders $50 and over.
Free returns to store (or via prepaid label) within 45 days.
Banana Republic and Gap Factory seem to be having a similar sale, but most of their stuff is out of stock.
They're also running a GapCash promo, but that seems to have limited utility (only able to use Gap Cash 11/29-12/4) - you can read more here: http://www.gap.com/browse/info.do?cid=99996. [gap.com]
Gap Cash counts from your original price (before 50% off).
They're advertising coupon code HAPPY for 40% off, but I was able to use coupon code FIFTY for 50% off (it is not advertised, found it on a coupon website).
Example of things you can buy:
Mens Twill Athletic Fit Pant (Stretch) [gap.com]
: $60 orig, $30 on fall sale - 50% FIFTY code = $15 + tax , and free shipping if your total purchase is $50 or more.
P.S. Try code WELCOME if you have a Gap Card for 10% off your purchase - haven't tried this myself.