There is a regularly scheduled chat on Thursday evenings about 8;30. When I go on that night, I always get there to find it empty or so I thought at first. Actually, I just have to sign out and sign back in again and it works fine.
Other than the Thursday evening chat, I don't there are regular ones, you could always post a night that is good for you to do this and ask others if they would like to join you. You never know it could turn out to be better than Thursday night.