In addition to the foam "vice", I have found the following vices, particularly the pana vice, extremely useful:
www.amatimodel.com
micromark.com
Amati Model - Keel Klamper - Tools for modeling
This special swivelling clamp holds and supports the model while assembling, painting and finishing. The adjustable jaws slide on the aluminium bar and the s...
www.amatimodel.com
PanaVise Bench Vise | All-Angle Versatile Clamp Tool | Micro-Mark
Work at any angle with the PanaVise Bench Vise. Features rotating, tilting head and non-marring jaws for secure clamping in hobby and repair work.
micromark.com