Tang Chi Wai is a composer for many songs including many of TVB's memorable theme songs. He recently had help from his friends to open a concert with many of them as special guests for his concert. Here's a video of Bosco Wong singing Myolie Wu's Fortunately and Leo Ku and Wayne Lai singing the theme for Rosy Business 2.
Here are some pictures of the concert including Raymond Lam, Susanna Kwan, Wong Cho Lam and others. Other guest artists on the various days included Niki Chow and Linda Chung.