I have a workbench made out of 2 x 4, 2 x 6 and 4 x 4 lumber. It is rough made (i.e. not sanded) and I've been using as workbench, though I think it's original use was sorting lumber sizes, as the underneath is divided into many sections.
It is very sturdy and well put together for strength, using screws. The top is made of 2 x 6. The dimensions are: 56" long, 34" wide and 36" tall.
I have now moved on from my projects and no longer need it.
There are actually 2 of them in case one is not enough! Both for $30