what is going on with Forex market? i have been following eur/usd and aud/usd and both of these are falling like a knife.

aud/usd is not supporting any technical stuff. any idea how far it can fall? is there any reversal insight?

The fundamentals are too powerful & they are overwhelming the technicals..
We maybe currently experiencing a apocalyptic moment (if Greece exits Euro & launches its Drachma), this event can literally change the global financial picture, so much so, that some currencies might collapse.
AUD is having the China effect.. (Chinese slowdown is having a serious impact on Australian economy)..
I would suggest to be extremely cautious in the pair trades (or rather move away & watch from outside at least temporarily)

Greece is a tiny country and it has shaken the whole world economy. I am not an economist but just curious to know what would happen if Greece exits Euro zone and introduces its own currency. I guess it is the trigger effect most of the people are worrying about which means other countries in the European union will also exit and introduce their own currencies.

When Greece exits, its the derivative on the Greek bond market where the problem is. The writers of the CDS will have to pay on the derivates, Its creates a domino effect on that OTC derivatives market. The main reason being the OTC derivative market is much larger than anyone can think off (somewhere in the range of 15 to 20 times the entire global GDP). It's this market where everyone is scared off.

There's not enough money in the world to bailout anyone of that magnitude. They are currently talking about ring-fencing Europe. But the unintended consequences & its implications are far reaching than anyone can imagine..

Here's something I found interesting
Who Loaned Greece the Money?
If Greece exits Euro, all of them will not get their money back, so most of them may go bankrupt (so to prevent tons of money will be prevented which will lead to inflation; if not than a consequences can be ......... I don't want to think off it)

http://demonocracy.info/infographics/eu/debt_greek/debt_greek.html

Still Greece should be kicked out of Eur with all debt written-off and all these lenders compensated by the printed money ...

Time of action is the key, avoidance and delay will be only more catastrophic or are they waiting for Greece to bounce back on her feet with that loan on her shoulders !! I wonder !