Can you repair a broken iPhone screen without replacing it?

I have an iPhone 4, and it has a very small crack in it. It isn't really impacting the phone at all, but if my parents see it i'll be in a lot of trouble. Since it's not a crack serious enough to need to completely replace the screen, s it possible to fix the crack? I know you can fix scratches in CD's with a special gel, is there anything like that for glass or touch screens?

Added (1). Also, if it isn't possible to fix it instead of replaceing it, could you explain why?

You have to replace it.

How else can you fix it? Just like a window, you can't repair it, you have to replace it.

If your contract is up, then just get 4S on a new contract, 4S is free on a 2 year contract so you can get a free upgrade that way. Thats better then putting money into an older version, you can even trade it in now and get something back for it.