Scratch

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I was one of the first people to make an OS (although, I didn't call it OS, I called it a computer). Now, with all the OS's out that have things like loading bars when they're not needed and there is so much focus on replicating it that they forget to include fun, the most important part. In this HUGE spoof of other computers you can:

Battle Viral Viruses
Join the Viral Viruses
Go on the internet
Rescue Crazy Joe
Complete Achievements
Check your mail
Download four things using limited bytes
Read a comic
Search Google
Scan for Viral Viruses
Destroy the World
Poke Letters
Read Word Documents
Shove a Pitchfork through your computer (okay, you can do that anywhere)
Learn About Us
Try to visit Newgrounds
Learn Life as a Duck.
And there's even more waiting in the game! So, what're you waiting for? No really, stop reading this text and click the hyperlink. Don't even bother reading this last sentence, cause it will tell you nothing.

CLICK ME