if it's the thick stuff you can cut it with a Jig Saw with fine tooth blade set on very slow speed to avoid clogging the teeth up (no heat on blade) no pendulum hth Tez
Up to around 4mm if you use a very sharp blade and straight edge,score deeply and bend over a table edge,with the scored side uppermost..Are you sure its acrylic sheet,because clear polystyrene looks very similar and isn't workable that way.If it has a metallic sounding ring when knocked its probably polystyrene.