In Reply to: hire mobile phone posted by marge on Tuesday, 13. October 2009 at 17:18 Bali Time:
There's a shop opposite the Jayakarta that rents mobile phones,
50 000 for a week. You pay 350 000rp, when you return the phone one week later you receive 300 000rp back (providing the phone is not damaged etc).
I know its not Nusa Dua area but thought it may be of some help.
As Imagem said, you can also buy a cheap phone in Bali.
Have left email open if you want any more info.