The FOURtress BUTT (which we are assured stands for Built Under The Top) provides a compact and elegant way to add some additional USB ports at the front to your FOURtress. The dock sits under the machine (keeping things tidy and compact) and plugs into the rear USB port. This provides 3 front facing USB ports (USB 3.0 for Raspbian/ USB 2.0 for RISC OS). The FOURtress BIG BUTT adds a Wispy V wireless Bridge unit to the mix.
The FOURtress BUTT costs 25 pounds and the BIG BUTT is 50 pounds.
RISCOSbits are promising some more BUTTs which will also fit some of their other machines.
They sent us some nice pictures of the new devices (which are thankfully SFW).
RISCOSbits website