Best Side-Scroller and platformer.

[CHONKY]

I'm looking for a game that is side scrolling and will bring back that old school gaming experience. Anybody got any recommendations.

[PentaPenta]

Well, obviously any of the mario games are classics.
Cavestory+ is a really fun sidescroller.
Super Meat Boy will make you punch a hole through your monitor.
Capsized is a really fun sidescroller too.

[Zefar]

Aquaria, such an awesome and beautiful game. So big as well.

[Silvio]

You should try Braid, too.

[Persephone Sapphora]

Are you looking for a Metroidvania or just a standard platformer? If just a normal platformer then I'd go with games like Trine 1/2 or Giana Sisters.. Unless you want that retro look..

[Metal-Slug]

Sonic 1/2/3/3&K/CD
Sonic 4 episode 1/2
Gunstar Heroes
Super Meat Boy
Ristar
Comix Zone

[schnitzeljaeger]

VVVVVV

[MESSATSU]

There are tons of great ones, some of my picks:

Limbo, Supermeat boy, cavestory+, Trine 2...

[Hotozi]

Try CortexGear AngryDroids
http://jh12world.com/cortexgearangrydroids

[Bundle85]

guacamelee is a fantastic take on the super metroid style.
super meat boy is probably my favorite platformer in years.
VVVVVV is a great 3 hour experience and priced accordingly.
Braid is fun and challenging, try not to look up answers as long as you can :P.

[J4MESOX4D]

http://store.steampowered.com/app/214560/

[Quint the Alligator Snapper]

Seconding the recommendations of:
* Aquaria
* Cave Story
* Guacamelee
* Gunstar Heroes (but I hear the Steam version doesn't have netplay)

Adding these recommendations:
* La-Mulana
* Mutant Mudds Deluxe
* Stealth B*stard Deluxe (spell it correctly when searching in the steam store)
* DuckTales Remastered
* A.R.E.S.: Extinction Agenda
* eversion
* Insanely Twisted Shadow Planet
* DLC Quest
* Eryi's Action
* Waking Mars

[xterminat0r]

Castle Crashers
BroForce
FEZ
Intrusion 2
Shank
Shank 2
Metal Slug
Never Alone
Deadlight
Bastion (not sure its a side scroller)