I made (well, assembled) my crackers last year, and I was really pleased with the results. I bought some extra large ones, and put in a miniature molton brown bubbles (30 l or 50 ml), lottery scratchcard, individual chocolate and the obligatory hat, motto and snap. They felt very upmarket for the bas e level cost.
What do I do this year? They will be for adults, primarily. The children's ones are easier - toy car/bubbles to blow etc.
Happy to spend about 5 or so on the contents of each cracker. The barrel length is about 13 or so cm if I remember rightly.