There are a few donator items (Amulet of Ru & Inn Coupons) in the game, but I am suggesting something a bit different. Something like Kyuubi.
Random Item for 1$ donation.
Sakura's Dairy
No exp lost during death (only covers forest fights, pvp, & pvped). Effect last for 3 game days.
Naruto's Purse
No gold lost during death (only covers forest fights, pvp, & pvped). Effect last for 3 game days.
Sasuke's Forehead Protector
Get extra exp bonus from all forest fights (not covering event creatures). Effect last for 1 game day.
Random Items for 10$ donations.
Tsunade's Coat
A higher chance of getting an item from forest fights. Effect last for 5 game days.
Jiraiya's Telescope
A higher chance of encountering forest events. Effect last 5 game days.
Orochimaru's Ring
No exp or gold lost during death (only covers forest fights, pvp, & pvped). No item damaged during Oro Kills. (does not cover forest fights, pvp, pvped or event) Effect last 5 game days.
*Note: You will only receive 1 donator item per donation. Donating 3$ will not get you 3 of the 1$ donation items.*