I have searched the web all over and for usb support, it is "not" possible due to the BGA model of the chipset.
Altho some more searching and checking diagrams, it "could" be possible.
Sofar, checked the bga package and checked wich pin goes where and sofar it seems that the 2 pins needed could be accessible underneath the pcb.
There also "seems" to be traces on the board leading to these two pins. J1 and J2 whereas J1=USB DATA + and J2=USB DATA -
If this is right or not i am not sure, but if someone could guide me in the right direction i'd be happy to try.
Wonder tho if there is anyway to "probe" out J1,J2 on the pcb?
I got "OpenWrt Attitude Adjustment r32481" kernel 3.3.8 on this DIR-600 B2 and eager to see if this is possible.
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I have a "theoretical" USB Trace tracked down, although i can not confirm it as of yet i wonder if someone else concur with the findings if it even are any findings. (self criticism).
According to the Datasheet of the chip, J1 is USBData+ and J2 is USBData-, the only visible chip marker is on the topside around the chip, the thin white line where it got one "bend".
Taking the conclusion that is the chip directional marker and flip it over it of course get reversed. Following that i have found this theoretical trace from the BGA with USB connections.
I hope there is someone else wich got a better light source and hopefully better eyesight 
to see if this would be a viable usb source.
Also i wonder if there is anyway possible to "probe" out the usb data signals like with gpio?
UPDATE: Found in Russian language on DD-WRT forum, -> DIR-300 B1, similar hardware, same bga chip. (google translated.)
UPDATE: Merged posts and deleted ol thread, bad topic format.
UPDATE: Conclusion is that there is no alternative usb traces to use. To be able to do ANY kind of usb mod you need either to desolder the bga chip and do as in the russian thread or use this method -> http://hackaday.com/2009/12/17/accessing-bga-pins/
Will update thread if i will be successful in any of the cases.
(Last edited by CraXyOW3 on 19 Dec 2012, 11:05)