Let me preface this by saying I am on the 'pay-as-you-go" plan with Cingular 'cuz I just don't have a history of making a lot of phone calls. I've been a PAYG customer for years and it's worked well for me. My average monthly cell "bill" was in the neighborhood of $8. Then I got a SmartPhone and started using my phone for lots of other stuff besides making phone calls. But, internet access can get pretty expensive pretty fast. And, now that I had a 'phone' that could do these neat things...I wanted to use it!
I know for PPC users this isn't "new". And for all of you with your unlimited minutes/data plans it's not a big deal either. But, for ME, it's HUGE!!! I don't need a PPC and have been really happy with the SmartPhone platform. Also, I can't justify a huge monthly phone bill just so I can "play". I wanted to see if having wifi built into my phone was everything I thought it would be. I knew I had access to wifi networks at home, at work, at school etc. So, it seemed like a nice thing to be walking around with a device that could access all these networks...at no extra cost. It's not nice...it's FANTASTIC! On top of all the places I knew I'd have access, turns out there is free wifi all over the place.
Here's a website that helps you locate places in your area: http://www.wififreespot.com/
But, in addition to those places listed, I've found bunches of other places. I've found many businesses that I frequent make it available to customers. The gas station I go to is one example as are the sports arena, the Target store, the muffler shop (who knew?), the computer store (okay, that wasn't a TOTAL surprise), the mall. You get the picture. The list goes on and on. I can hop on to wifi just about anytime I want. The speed is great (of course) when compared to GPRS. I don't hesitate to click on a page for fear about how long will it take to download! Like Emiril says...Bam! There it is...on my phone just like that. I did the speed check and it was 1000-something! Used to be 30-35 on my MPx220
. The first time I checked the wifi speed I chose a 200k file like I always have done and the site came back and told me to pick a bigger file 'cuz the speed was too fast to measure. 
I don't think it is worthwhile to pay T-Mobile or ATT for their "hotspot" service. I guess it would give peace of mind to 'know' you could go to one of their places and be guaranteed a connection. But, around here at least (Southern California), it just is not difficult to find access. It seems to be just about everywhere!
Today, the latest fun thing I did, for the first time, was stream radio and listen to it via my BT headset while I ate lunch at my favorite cafe (a free hotspot). Cool.
