Monopoly: Do I Collect Rent If I Am In Jail?
Being in jail only prevents you from moving, and does not prevent you from doing any other action, including collecting rent. The rules state:


  Even though you are in Jail, you may buy and sell property, buy
  and sell houses and hotels and collect rents.


This is a very popular strategy late in the game, as the less you move, the less likely you are to land on your opponent's properties.

In addition, the rules specify that the only times you do not pay rent is when the property is mortgaged or if the property owner does not ask for rent before the next player's turn.