For me, it's not the actual speed I need but fairly low latency. I moved all my dev stuff to the cloud (Azure VMs) last month, and I SSH to the server and do some work there. The good thing about it is that I do not need to actually download say Ruby or Postgres over my network. VMs have crazy high speed so
apt-get anything is blazing fast always.
I tried programming on much slower connection but with good ping, it actually feels really good too. Latency more important than the actual throughput.
The provider/cost is Orange LTE, 2 year contract, 79PLN (15 GBP) / month with 150 GB monthly data limit (night transfer between 24-08 unlimited). I think that's pretty good deal, just need to restrain myself from too much Netflix (which is good to do anway )