Mine is similar to LenS above. I probably got the idea from him originally. I use a small 12 volt pump controlled by a toggle switch on the side of the cabinet and a small 2.5 gallon tank underneath that is easily removable and refillable. A second blue tank is the grey water collection tank.
You can see the switch on the side between the two hooks and the TV coaxial plate. I use the switch when I want more water (like when filling my coffee maker pot) and use the little pump handle on the faucet when I want a small amount (like when brushing my teeth). I use the hooks for hanging a bag with magazines and reading material and the closest hook for a plastic bag for trash.