Luke wrote a huge chunk of the New Testament, more than anyone else. He also wrote more about prayer than anyone else. Of the nine times he reports Jesus’ prayers, seven of those aren’t found in the other gospels. Luke alone records the three parables on prayer: The unjust judge (Luke 18:1-8), the Pharisee and the tax collector (Luke 18:9-14), and The Friend at Midnight (Luke 11:5-8).
Luke records believers praying in the middle of the day and in the middle of the night. They pray alone and in groups. They pray in moments of joy and in distress. They pray in houses, on rooftops, on mountains and on beaches. Click and have a look:
Source: Prayer in Luke-Acts, by P. T. O’Brien in Tyndale Bulletin 24 (1973) 111-127 [PDF]
(For the nerdy, yes, I was inspired by a much-hyped computing interface 🙂 )