So I know this is kind of late, but I just lived through a three-day power outage, so stay with me, because it's story time. *a-hem*... 
 
Many moons ago, in a time of great darkness in the world (read as: when I owned a 4 year-old Macbook), I learned of Steam. Now, when I say I "learned" of Steam, I'm not saying it was completely new to me, I've been around the internet a few times in my day, but I had never given Steam any serious thought. Up until a few months ago I had primarily been a console gamer, sticking to my beloved 360 for my electronic entertainment. In my naive mind, I thought "Why not take advantage of this delightful "winter sale" they're having?" And took advantage of it I did. I immediately installed Steam and purchased three games: And Yet It Moves, Diamond Dan (which actually proved to be more fun/frustrating than I thought), and Penumbra: Overture.  
In a cloud of childlike innocence, I set to work installing these games. After installing AYIM, I left the others to finish downloading, double-clicked the desktop icon, ready to embark on a new adventure in gaming. That's when things took a... turn. I can only describe what happened to my little old Macbook as catastrophic. It heated up, the screen flashed and it made noises I hope to never hear again. 
And then it shut itself down. I'm still not exactly sure what happened, but I assume that AYIM caused my computer to crash. Let that sink in for a second. It's not like I was playing Crysis or anything. On any other computer, running AYIM doesn't seem to be a problem. I'm no expert, but I can't imagine it took *that* much power to run. It took an hour or two, but I was able to get my computer back up and running. I didn't continue downloading the other two games, mostly out of fear. I've since upgraded to a newer computer and switched to Windows, re-installed my modest Steam library and have learned from my experience. 
About a month ago, I got a new computer. I spent the first few days installing necessary programs, or things I felt I needed. After getting over the loss of my favorite Minecraft world, I turned to Steam. Could I learn to love again? It had hurt me in the past, but I hoped that I could change things. At first,  I installed Steam for only one reason, I had heard a lot of hype about Terraria, and being a Minecraft fanboy, I needed to know what the hype was about. I purchased, installed, and played. Things went beautifully. But was I ready to give AYIM another chance? I was. Cut to a day later, I had installed and beaten AYIM, I was so pleased with myself. That was the start of a beautiful friendship. 
That's where the story ends, it wasn't so much about the Steam Summer Sale, but it was about my rekindled love for Steam. Thanks for reading this block of text, but just in case you didn't...
 
TL;DR Had a shitty Macbook, installed one game, almost destroyed my laptop. A month later, everything went better than expected.
 
P.S. If anyone's curious, I didn't buy as much during the Summer Sale as I wanted to. I bought the entire Sam & Max library on one of the last days. I also bought the Puzzle Agent games, although I haven't installed them yet.

In terms of sales from Steam, I remember buying STALKER and then felt bored and sort of uncomfortable with it. At least it was $2.

I have such a backlog of games I got for, like, a dollar that I feel bad about wanting the games that I really wanted to play. "I just bought ten games, why would I want another one?!". Oh yeah. Those 10 are shit. 
 
Such are the trials of perilously low prices.

I think one of my biggest problems with the Steam sales is how often I find myself considering buying a game again just because it's so cheap. Like during the last one, I caught myself thinking: "Gee, I've already completed the 360 version of Just Cause 2, but maybe I want to buy it again for 3 bucks." Sigh... first world problems...