The night life of Lucknow is very different it doesnot involve clubbing e.t.c, but it's fun and a good experience to take a stroll on "Hanuman Sethu Bridge"; the whole of Lucknow is lightened up and it's peaceful and calm.
But please be careful.. too late nite walk could be unsafe too.
Well! There's a small and calm temple on the bank of river Gomti, name as "Sunny Temple", I generally like visiting this place in the nite, almost all saturdays; it's very peaceful and calm.
It's a great place, if you have friends along and some groundnuts to eat. Perfect satisfaction of mind and soul.