I was in the market for a notebook mouse for my forthcoming Macbook Pro and found this great deal at Comp USA. Its aluminum so will look great with powerbook or macbook pro. Im using mine now and its much more sensitive and accurate than my plugged in HP optical. As well as being lighter. Check it out:
http://www.compusa.com/products/product_info.asp?product_code=317046&pfp=srch1
http://www.compusa.com/products/product_info.asp?product_code=317046&pfp=srch1