Many old tubes sleep in my country house, since the old times when my father used to build vacuum-tubes radios in his green days. There are also lots of miniature 7-pin EF95 pentodes, that were used in high-frequency amps.
Now people round the globe is using them for audio applications... so I decided to try out a low-anodic voltage circuit. With small signals you can't drive the valve into the distortion zone, therefore I added a FET stage. I've also inserted a pot that moves the pentode's operating point, but its effect can be noticed only at high distortion levels. 

It works sweet, it's really easy to build – and it does not sound bad at all!

On stage I'm using it with a 'burglar alarm' type lead battery not to have to plug one more "brick" PS.