No, no! I don't want to use it for the AC shi*t, it's just a general question... for example, I may be returning to US in a few months, so will I still be able to use my old SSN -- WH purpose only!

Or does the SSN lasts only a few years, and then you need to renew it? ... Something like that.
P.S.: Seriously, I cherish it! The small card is always there where I keep my best belongings!

I could've easily gone on to stay further in US as I was getting a lot of great job offers then, but that would've meant that I jump my contract with the company that gave me a break in US. I left then and honored my contract and the 'value' of this little card! So why would I lose this over something very silly?
Just wanted to know the answer all the time, and with this thread, the old qt. popped up suddenly.
I don't want to waste it on any online sh*t programs, A*C esp!