Good games under 10$

What about Fallout 3 or New Vegas?
Heard many good things about it.

This collection costs $10. 3 outstanding games that will last you for more than a week (unless you live in front of your computer).

Payday2

Super House of Dead Ninjas 1.75$, fantastic game (98% positive reviews) /
also you can test or even play a lot! ;) pre-Steam version, online and for free http://games.adultswim.com/super-house-of-dead-ninjas-action-online-game.html

South Park: The Stick of Truth 7.5$

some Codemasters title, DiRT Showdown for 3$ only! + first GRID for 2.6$

Payday The Heist 1.5$ or Payday 2 for 5$

Squishy the Suicidal Pig 0.14$ :) little but really funny platform game

Super Crate Box Ok, it might only last a weekend instead of a week. But it's hard to go wrong for the price of Free

Original Deus Ex + free revision mod. Said mod is what I plan to spend the next few days with.

Knights of the Old Republic might be showing it's age a bit on the tech side of things, is still one of BioWare's finest.

Hitman: Blood Money If people were disappointed by Hitman: Absolution, it's mostly because they've been spoiled by how much more open-ended it's predecessor was

One Way Heroics Quite entertaining JRPG/Rogue hybrid. Currently on sale for ridiculously cheap too, worth giving a shot if you like either JRPGs or Roguelikes, must have it you like both genres.

Red Faction Guerilla is one of my favorite open-world games, for the sheer potential for mayhem it has.

Duck Game

fear bundle:

https://www.bundlestars.com/en/bundle/fear-bundle

Lyne : http://store.steampowered.com/app/266010/
Awesome puzzle game for 3€... BUY IT !

Melody's escape : http://store.steampowered.com/app/270210/
Really good rhythm game, it's early access but nearly finished and highly playable, a lot of different difficulty settings if you never played such games. High replayability.

Paper Sorcecer : http://store.steampowered.com/app/263560/
Sweet old school RPG for 5€, often in sales for less then 1€ on the humble store...!

Gunpoint : http://store.steampowered.com/app/206190/
Clever puzzle game, with funny story. A bit short though, but you can create and share your own lvl through steamworkshop !

Ittle Dew : http://store.steampowered.com/app/241320/
Really funny puzzle game ! The story has some casual puzzle but an optional dungeon will give you some hard puzzle to solve.
Also the story is solvable different ways.

I'll also add Reus : http://store.steampowered.com/app/222730/
It's not a new game, but if you don't own it, you should ! It's not a god game like advertised though. It's a puzzle/strategy game and late game is not casual at all ! The steam tags are all wrong on this game :(
But it's an awesome game anyway :)

Half-life series. start with the first one (duh) then do the side series (blue shift, opposing force) then move to the second series. (total amount for all the games is like $40, but the first one is $10, and if you buy during the summer sale, it's like $12. ) Enclave (never played the Game, but sounds good.)

CS:GO during a sale.

Gotta agree with the above South Park

Fez-9.99-http://store.steampowered.com/app/224760/

FTL-9.99-http://store.steampowered.com/app/212680/

Game Dev Tycoon-9.99-http://store.steampowered.com/app/239820/?snr=1_7_15__13

To The Moon-9.99-http://store.steampowered.com/app/206440/?snr=1_7_15__13 (short but great story)

Unholy Heights-3.99-http://store.steampowered.com/app/249330/

Undertale-9.99-http://store.steampowered.com/app/391540/?snr=1_7_15__13 (I've never actually played it but my friends can not stop praising it)

Also if you want some free games I can vouch for

AdVenture Cspitalist-http://store.steampowered.com/app/346900/?snr=1_7_15__13 (Fun addicting clicker)

Mitos.is-http://store.steampowered.com/app/389570/ (Agar.io clone on steam)

Bonus: if you ever want a good cheap time waster get achievements in games you already have

Save $50 more and buy Fallout 4.

I'd go with Terraria if don't have it already. If you catch it on a sale it will only be 2.5 or less (9.99 regular price)
If frustrating games are your thing then I would highly recommend Volgarr the Viking. It won't be a short game for sure but watch a few videos before getting into it

I see that you never played
The Binding of Isaac (+add-on Wrath of the Lamb)

It is the only game I have a level 5 badge.
It costs less than what you have and my playtime is about 200 hours (more than a week has).

Here's some games I like, although some of them are really short. To The Moon is less than 2 hours, Brothers is 4-5, and The Stanley Parable is around 3-6.

Machinarium
Fez
To the Moon
The Longest Journey
Half-Life or Half-Life 2
One Finger Death Punch

If they go on sale:
Brothers - A Tale of Two Sons
Antichamber
Mirror's Edge
The Stanley Parable

Edit: You can also use this search on steam to find all games that are under $10 and listed in order by their steam rating: Steam search

Hearthstone? Its free and it can be fun.
TF2 is another fun game that is free.
Path of Exile is also a good option if you like ARPG.