It's interesting to note how this has been changing over the years. A "must" is mobile internet, for weather, notams, contacting airports, etc, and it has been a "must" since I started flying abroad in 2003. But back then I used a Nokia 6210 phone connected to a laptop via an RS232 cable, with a 9600 baud dial-up connection to my home ISP To be fair I could send faxes...