advise on smartphone

hi, i'm just looking for some simple advise on a smart phone that can do everything i need it to, and hopefully not make me broke

I'm looking for an international coverage plan with a direct internet connection that won't break my bank. Ideally i'd like to store my media online on a secure network and access it for videos and music. Also, I'd hope to be able to swap out local SIM cards and possibly just pre-pay them for local calls while abroad. For calling US, i'd hope to use skype or instant messaging etc.

Do plans such as for the helio ocean or blackberry global phones charge you for constant internet connections while abroad? I'm just looking for the best way to find a reasonably prised smart phone that can do the following while traveling without ridiculous connection / download fees:

constant connection to the internet
take pictures / videos
stream music / video from personal servers
IM / chat
skype
GPS

The ocean and new blackberry both look good, i'm just trying to figure out if I can go travel europe etc and have good options for using the internet for music / videos without dying from the cost.. I'd like to be able to replace my phone, mp3 player, and camera with a smart phone, but only if it'll be practical (particularly skype would be incredibly helpful for international calling while abroad) - just wondering how exactly this all works

thanks in advance

edit: i guess after more looking my biggest question is which companies actually offer truly limitless online access and decent bandwidth at a flat rate. i heard that helio offered 'unlmitted' access that was really quite small and i saw that prices for the blackberry world edition were quoted at 2 cents a kilo byte, which would be quite ridiculous for what i intend to do.. advise? thanks a ton