Looking for affordable TodoMatrix-only device

[sivan]

Hi. I currently own a non-BlackBerry smartphone but would like to use TodoMatrix.

I don't think any BlackBerry model would be a good substitute for my current device so am looking at getting the cheapest, most basic BlackBerry that would work on the most basic service plan just as a dedicated TodoMatrix device to carry with me along my other smartphone.

A data only or limited data plan would be fine, but I'm not too familiar with how BB gets on data plans. Do they require BIS? If so, I can't find an affordable plan for basic data usage.

Suggestions for a basic BB with a limited, essentially just a connected PDA, non-contract data plan would be very appreciated. Thank you.