Cheapest Voip Services

I’m a huge internet nerd, and was looking around for a decent priced internet tablet. I came across the Nokia N800 for $225, so heres where my question comes in;

I’m looking for a good device that can surf the net at reasonable speeds over wifi, that can read PDF books with a display that can actually see the words, and something that can play the occasional song or two. Also, a VOIP service would not go amiss.

Anyway, is the N800 worth buying, or should I skip it and look for another product? Thank you!

Kristeen