Right, after some chats and a bit more research it would seem i have the following options:

Mobile broadband dongle with a UK company then pay anywhere between £1 and £7 per MB up to a usage limit.

Mobile broadband dongle with a local company in each country I go through – haven’t been able to find out exact prices for that yet.

Use wireless hotspots – it seems there is a far better network of these than I had imagined – my bad for being a bit patronising to countries such as Serbia, which apparently have a quite good wi-fi infrastructure.

Use internet cafés – i’ve been in internet cafés in the Himalayas so am sure that I’ll be able to find them to serve me needs at least once a day over the summer – however I’d like to have constant access when required with ICs just being used to supplement this/keep the cost down.

BGAN – would probably be hideously expensive but would provide more consistent coverage.

I image in reality I will end up with a dongle, mapping out reachable hotspots and also seeking out the odd internet café here and there – hopefully this should keep me covered.

I’d appreciate any further words of wisdom anyone might have.

And as for why I need this level of internet access…well…I can’t say just yet.