I am not sure if many know about this site, but I figured I would mention it here to maybe help save some people some money over time.
I came across it while searching for a coupon code to a program and this site had the program at 60% off. Of course, as life works, I missed out by a few hours.
The site is called <span class="bold">Bits du Jour</span> and they seem to have daily sales on software that last for nearly a full day before the software changes to something new.
You can look ahead and see what is going to coming so you have about 5 days advanced notice, if you register with them. If not, I think it is like one day ahead.
Anyway, I figured I mention it as sometimes it is known software that is marked many times 50-60% off of retail.
I have a feeling that many of the titles are Indie programs, but since I do not know them all, I cannot say for certain.
That's all, Enjoy! :o)
EDIT: Wording

Or you could just go to Giveaway of the Day and get paid software for free for 24 hours (you have to install the software before the 24-hour period ends, but after that you can use it as long as you like provided you don't uninstall it).

I'm a big fan of [url=www.retailmenot.com]RetailMeNot[/url], where people can post discount coupons for all kinds of websites. Many of these coupons have unlimited uses for the duration of the promotions, which is great. I use them whenever I can.

Well, this is interesting. Maybe others then have come across other such sites that could be listed here.
I still like Bits du Jour and how the developers typically talk and answer questions about their products before you buy it..