FAQ: Can I use two or more of these 3-port Hubs to connect several FW800 devices to my Mac?

Yes you may, but you might be better served using the Unibrain five-port, rather than the Unibrain three port hub. Here's a topology using two three port hubs:

              Hub_1
HOST --- = p1 |
              | p2 = --- DEVICE         Hub_2
              | p3 = ------------  = p1 |
                                        | p2 = --- DEVICE
                                        | p3 = --- DEVICE

This works out of the box for self-powered FireWire devices. Bear in mind that any bus power devices will require an optional power supply. Also, the total device count on a single branch cannot exceed 16, and understand that aggregating multiple devices on a single port does create a potential for over-saturating bus bandwidth if several high-performance (e.g. HDDs) devices are sending data at once. However, for most uses, tiered hubs are fine. Lastly, put your slowest devices on the end of the chain.

Hope this was helpful.