A great way to expand your range of accessories is to pool your costume jewellery with friends and family. Whereas your best friend might be reluctant to lend you her diamond necklace, she's more likely to be happy to share her cubic zirconia piece. Its relatively low value means you're more easily able to swap with others without the worry associated with high value items.
Fancy Dress
Much costume jewellery is inexpensive enough to treat yourself and others without having to justify it with an occasion or special event. This means if you're out shopping and happen to come across a bracelet that you simply must have then you can have it without suffering retail guilt. Likewise, if you want to thank someone for a favour then costumer jewellery makes a inexpensive, but desirable gift.