Tracking digital sales events

Out of curiousity I added all PSN games I plan to get to the shopping cart yesterday and the total amount was astounding. $277.xx.

None of them discounted, of course. The question is do you guys know what is the best technique to catch all the sales eventes for Steam, PSN and XBOX Live?

What are the key holidays in the U.S. when I should be expecting a sales? Start of seasons, public holidays which these services put on a discounts, etc.?

The following is just from what I've seen over the years:

Most sales on PSN are usually through PSN+.

Beyond that, they're pretty random, although their Summer PSN Play thing is becoming common. Which gives you cashback for buying multiple.

Microsoft pretty rarely discounts anything.

Steam usually has one in Summer and one around Thanksgiving time, then there's the daily and weekend deals.

@Eujin: What? MS has a weekly sale... every week. Plus if you install that Sales and Specials App, you can get new deals every day.

@OP: You can check the PSBlog and Major Nelson's website for upcoming PSN/XBLA sales respectively.

@Enigma777: My apologies. I actually booted up my 360 as I thought you were crazy at first, but it's totally there. I think I got so tired of dealing with the new dashboard that I quit looking.

@darpa: The PSBlog is definitely a good place to check for sales, as they'll almost always have posts on them so you don't have to go digging through the store.

I haven't personally seen anything from Major Nelson recently, however as I missed the sales stuff entirely on the 360, who knows what else I'm missing.

Sometimes subscribing to your favorite publishers can get you informed on any upcoming deals. With Atlus, which is actually the only newsletter I'm subscribed to, they sent out e-mails informing me that the Persona games on PSN were going to be discounted for a month or so.

Also, here's a direct link to the PlayStation store stuff: http://blog.us.playstation.com/tag/playstation-store/

And here's a direct link to Major Nelson's discounted stuffs: http://majornelson.com/?s=discount

Thank you, sir and madam. I'll try every suggestions.

CheapAssGamer have some pretty cool systems for tracking prices, I think that goes for digital as well but I'm not sure. Click the pricetracker in the heading.