If you don't mind the inconvenient location (lack of proximity to attractions and dining scene) or the Dickensian-orphanage-meets-the-tropics vibe, this place will do in a pinch. Non-members have to sign up (KSh500) to use this YWCA. It's primarily for women, but there is a men's floor as well. There's a cheap restaurant that's popular with Kenyan students.
YWCA Mombasa
Mombasa