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You can do it quite easily with almost any usb key, external usb hdd, sd card or any media the PS3 accepts, you just need to find an option file someone has already prepared for use on the PS3 and place it within the correct directory, then you can select it on the PS3 and copy it to the memory card.
A quick google will likely find you a option file you can use, if there isn't already one floating around this board somewhere.
I use a ps2/ps3 memory card adapter, its cheap, quick and easy. Just put your ps2 mem card with the option file into the adapter, it connects to the ps3 using the usb cable that charges your controller, go into ps2 mem card utility in the ps3 menu and you will find the mem card in there, open the mem card and select the option file then copy it to your selected destination, either an existing virtual mem card or a newly created one, if you create a new one do it before you connect the ps2 mem card, you can name it whatever you want, then whack your option file into it, dead simple