I recently purchased a new macbook pro and kept my macbook for my wife. I get my internet through my cellphone and Verizon broadband. I am using the Pro as my "base station" and sharing my internet with the macbook via "internet sharing"/ airport. I can't seem to locate any info on the riskiness of this, or not, and can't seem to figure out how to initiate WPA or anything else for that matter as protection. I live in a very rural area and am reasonably certain there's low risk of any crackers close by. What about VPN? Is that something I should be considering? I guess a risk assessment under this setup is first and then any mitigating actions next. Feeling vulnerable and the more i research the more confused i get, and the more vulnerable......perhaps unwarranted?

MacBook, 2.1Ghz, 2gb, OSX 10.5.6
MacBook Pro 2.5, 4gb, 10.5.6