Well, there's worse things you could be spending money on...like gambling, drugs, or other women. <img src="/ubbthreads/images/graemlins/laugh.gif" alt="" /> I'd tell her you're going to thin down the collection (perhaps to buy her a Xmas present?) sell a couple crappy ones, find a good hiding spot for the rest, and only get out one at a time so she doesn't know how many you have.

For future purchases, you can order with money orders, a credit card, or pre-paid debit card she doesn't know exists. Then have the knives delivered to a P.O. box in your name she doesn't know about, or a friends house or your place of employment. Then sneak them home and hide them. If she finds a new one, it's "an old one I've had forever." <img src="/ubbthreads/images/graemlins/laugh.gif" alt="" />