Tip: control your roaming costs with Droam
This is going to look like a "sponsored message", and in one way it is, but also I really think this might come in quite handy for you as well.
Are you planning to go on a trip outside of your own country (to Barcelona soon, for instance :-) you might be interested to know about a Dutch firm that offers an interesting possibility to control your roaming costs. It's called Droam.
It all works with a WiFi dongle. That has a simcard that will connect with the strongest network in the country you're staying in. You'll just need to connect your smartphone to the dongle and you'll have a lot of data at your disposal for a fixed price.
For instance, going to Barcelona during the MWC, you will have to pay 50 euros to get 1GB of roaming, that's 1 euro for 20MB, or 0,05 eurocents per MB. Of course it depends on what you plan to do, but it general that should be enough. You can also share the same WiFi connection with several (up to five) other devices.
Here's a short animation explaining the concept:
I have been using the Droam for years already and I've always been happy with it. And yes, you guessed right, Droam is "sponsoring" the device during my stay at the Mobile World Congress, so I can keep sending those Nokia 808 PureView shots from Barcelona without having to worry about my phone bill.
So maybe it's an interesting service for you to use as well, also if you're already planning a holiday - and that doesn't have to be in Europe, since it's available in more than 50 countries.