Flash, the residual on an '08 is around 67% for 24 months and 58% for 36 months. Lease interest rates are running around 6.50%, plus $750 up front fee. Compare rates to financing and remember that a home equity line at prime today is 6% and you can deduct the interest. Buy or lease and you'll bear the heaviest depreciation in the first few years. If you plan to keep the viper a long time than you can lease at a longer term, but in leasing its costly if you try to end it early. Leasing is just another form of financing, if you make an educated decision on the rates/terms, you'll see that a couple of advantages to leasing are the stop loss (guaranteed residual) and you only pay sales tax on the payments not the purchase price. My advice for leasing is make sure you plan to keep it the entire term of the lease.
For me, I pay cash and/or use a home equity loan for viper's, for daily drivers I lease 36 months and change cars every 36 months.