A way to gift cars and still keep them
Have a USB stick handy
Exit the game, and insert the USB stick
go into 'saved data utility (ps3)' and select the GT5 game save from HD
Hit the Triangle button and select copy
It will ask to copy to the USB stick, ok it
Now restart the game
go into your garage and select the car you want to give away
choose your friend and ok it
you will now have a space in the garage "empty no car"
if you sent a standard car click on the premium tab
if you sent a premium car click on the standard tab
(not that important, but i found you may lose the car icon if you don't do the above)
Now exit the game again
Go to 'saved data utilty (ps3)' and select the USB stick
select the GT5 game save on the USB and hit the triangle and 'copy'
It will ask to overwrite your GT5 game save on the HD, click ok
Restart the game
go into your garage
and the car is still there :)
courtesy of StEaLtH