I use a thompson flat bottomed vise. Easy to move as well as pack as it comes apart in two pieces. A friend of mine took one of the table clamp vises and welded a stell plate to the bottom to create the same effect. Maybe put felt on the bottom as to not scratch the shite out of the table your working on. Tackle boxes make excellent storage for fly tying gear and materials. Everthing in one place just pick up and go. Nice for camping trips or tying with friends and such.
Hope this helps,
Mike