One of my least used rigs (it has still to be used at this QTH!) is my 4-band Elecraft K1 CW transceiver. This covers 40m, 30m, 20m and 15m CW at up to about 7W. It has the auto-ATU built in so just needs a 12-13.8V supply, CW key and end-fed antenna to be on the air.
At my old QTH it has worked lots including the USA on all bands with a simple end-fed wire antenna down the garden. I really should consider selling it or trading it in as it is not being used.