Airport shuttle? (Tbilisi)

Dear all

Next Wednesday night I have to go and fetch my friend at the airport. Since I won't have any luggage with me, I thought I'd take the bus, but unfortunately his flight only arrives at midnight and I'm afraid the last bus might be too early for me. I don't want to take a taxi as a taxi there and back will be a bit costly (we'll have to take a taxi from the airport to my house). I've heard rumour of a 24-hour shuttle service costing 2 GEL that leaves from Freedom Square, but can't find out any more information about it. Can anyone assist? What is their schedule? Where exactly does one catch this shuttle? Can you recommend any other transportation?

Many thanks,

Amelia