serial data buffer?

hi,

looking for some advice please.
I am setting up a swipe card reader for a project, my data is usually fed direct to the pc, however I would like to know if it is possible to set up some kind of storage / buffer to hold data being recorded while the PC is switched off. I have seen off the shelf "mobile swipe readers" which must do this, just want to know if this is possible to set up from a hobbyist / newbie perspective.

any advice / help on how to purue this idea would be greatly appreciated.

Yes this is possible. Many microcontrollers come with EEPROM or data flash memory that will retain its values even if your microcontroller loses its power.