Can anyone tell me what this is?

[michaelsyer]

im pretty sure this is making a horrible beeping noise every time I start my car.

 

[petercronin]

I assume you mean the black plastic round bit on the side of the intake, if so - pcv valve. Very common for them to do this and they can be cleaned out or replaced very easily.

 

[Daverb]

Thats a nice throttle body. Is that on your car? Still electric?

 

[Jimmy]

This guide will tell you how to clean out the PCV valve, if you want to go down this route, rather than replace it - it really does help. Just gets gunked up over time.

http://clio197.net/threads/cleaning-pcv-valve.54918/