Can't see these on the Comet website, but worth a check in your local to see if they have any instore.
My local store had the following:
~ Aluminium DS / DS Lite Cases reduced from £14.99 to 99p; (see photo)
~ Clear Blue / Clear Pink DS Lite Protector cases 99p;
~ PSP Key Essentials Pack (incuding Hard Storage Case, USB Charger and Data cable, UMD Case, Spare Analogue button, Wrist Strap) also for 99p (see photo)
I'd definitely recommend the Aluminium case, especially if you are going on holiday - it's got space for game cartridges and has a carry strap too...
See posts below for other 99p things that have been found in local Comets....