Ok, this recently happened to me, but I know for a fact my Treo never got wet and there's no burning sound or smell.
One day I was @ work, I used it at lunch without issue. Then around 2pm I seen the screen light up (figured it was a text message). I couldn't acknowledge it at the time but about 10 mins later I tried to read the text. When I hit the button to turn on the screen, nothing happened. So I did a soft reset and it wouldn't move past the Treo boot screen logo. I tried this about 4 more times to no avail. So I tried doing a hard reset (several times). I get the hard reset option, press the UP button and net the same result.
Now this happened on DEC 20 and I was leaving to go to MI for Christmas so I HAD to get a new phone. I got a Mogul (love it), but I'd like to get the Treo working so I'll either have a backup or I can give it to one of my buds.
So, any ideas???
If I can't get this working, I'll have a sync cable (modded to charge while syncing), wall charger, car charger, battery (stock), audio adapter w/ earbuds and a non-functioning 700WX FS.