Colombia

Comcel
SimCard can be bought in several shops with the Advertising of Comcel on it. Price is 5000 COP, worth around 2 $.

Data Rates
can be activated for 1 (4640COP), 7 (29.000COP), 15 (52.200 COP) and 30 (80.000COP) days

Text an SMS to 464 with "1", "7", "15" or "30", depends on how much days you want to activate.