There is a fundamental conceptual difference between interest payment and rental/lease payment which I have tried to highlight. I am sorry if you and yoboy are not able to grasp it. You should consult a good book on Islamic business ethics and finance.
Once the person has paid off the full price of the car the leasing company is free to "gift" the car to him or sell it for a token price. This particular point has never been a basis for controversy.
Financing is not against Islam. Islam just places some conditions which need to be incorporated in the scheme. Products and services which comply with, incorporate and meet such conditions are considered to be compliant with Islamic principles. It is RIBA (usury) and GHARAR (uncertainty/ambiguity in transactions akin to gambling) which are two of the main important phenomenons prohibited according to principles of Islam. Both of these are avoided in the case of leasing.
Again, i would like to restate:
1. This is a very deep and serious topic which deserves to be studied. Authentic Islamic textual sources and reliable historical accounts need to be examined carefully.
2. It is the consensus of a vast and diverse majority of Islamic thinkers that leasing is in principle not against Islamic principles.