What can I get on the sale for under $2?

Gently pets you

Anything here.

Outland
http://store.steampowered.com/app/305050/

http://store.steampowered.com/search/?filter=ut2#sort_by=Price_ASC&filter=ut2&page=1

How To Survive is on flash sale for -95% (and after the flash sale it will be -90%)

Portal, To The Moon,Super Meat Boy, LYNE,Castle Crashers and Trine Enchanted Edition

I'll gift you Metal Slug 3 if you want it.

I would get get BEEP http://store.steampowered.com/app/104200/
and polarity http://store.steampowered.com/app/315430/

They are both 19 cents right now, they both have ~90% positive reviews, the gameplay is well worth the cost, and they have cards so you will make most of the cost back.

Not sure what you are interested in...Brothers - A Tale of Two Sons looks great to me and could be around 1,49 euro (I speculate because this price is based on previous sales and I really can't say if it will be discounted that much).

First topic? Burn the heretic.

To answer the question: Outland. I saw it's been suggested top, but.... Outland.

And a few cheap games to earn some money back from STC.

http://store.steampowered.com/app/219640/

Totally worth it.

-How to Survive - Storm Warning Edition 0.99$
-Buy ORION: Prelude 0.74$
And:
http://store.steampowered.com/search/?filter=ut2#sort_by=Price_ASC&sort_order=ASC&filter=ut2&page=1

How to Survive Storm Warning Edition is the current major title in that price range but expect other ones to be that cheap with daily deals or flash sales so if its not your cup of tea just wait you will get a game on sale that you will probably like since sales change each day and we have 7 days left.

What about Rollercoaster Tycoon Deluxe?

http://store.steampowered.com/app/2500/?snr=1_7_7_ut1_150_5

Shadowgrounds quite fun topdown-shooter

Bad Rats

Brothers - A Tale of Two Sons

http://store.steampowered.com/app/225080/

If you can wait until enforce sale (last days) maybe Sir, You Are Being Hunted will resurface wiht it's 2€ price :)

One Way Heroics is awesome, but keep in mind that OWH+ is supposed to come in the future, and I don't know if it's going to be on Steam as a separate game or just as a DLC.

If you like oldschool iso RPG Avernum trilogy is -90%

The albino hunter + how to survive storm warning edition + deponia, thats what i took personnaly (i had around the same amount on my walltet :D (brofistofcheapskate)

Brothers - A Tale of Two Sons
How to Survive Storm Warning Edition
Deadly Premonition: The Director's Cut
Safecracker: The Ultimate Puzzle Adventure
Trine 2: Complete Story
A Story About My Uncle

Some of them are over 2usd. I just got how to survive and deadly premonition, played safecracker and Trine 2 (and love them). But it's all up to you, i don't know what you like :)

I recommend also (In addition to some of the games named):

One Finger Death Punch --> It's like 2,7 or 3$ but on 50%, so maybe 75% during this week, what a great game it is.
To The Moon: if you like this kind of games, its short, but the story is very well written.

buy some game for 19cents that have cards....some of them are playable and you get cards=>sell them=>you have 15 to 20 cents back for another game to try :-)