So can we preserve things in space?

ok so i read another question..asking what would happen to something that somebody dropped in space...like a toolbox.And the main answers were that it would just keep going around in circles forever.So theoretically could we put things in space for future generations to discover when we are all long an gone? a bit like a time capsule? Obviously we don't want to clutter space up with all our rubbish...but i was wondering if theoretically this would work?