Looking for a car rental service in europe

I go abroad to europe and I'd like to rent a car to travel to all the different countries, can someone recommend a good car rental services, which is available in different countries?
Thanks!

If you are looking for a car rental service in Europe CityCarRentals.com is the perfect choice for you which provide the best car hire services at an affordable rate.

For comfort trip in Europe it is better to hire cars from our service. We provide quality service for satisfying our clients. www.koratcarrental.com

In US you can ask us for car rental as a taxi or cab provider, we are ready to provide for short term and long term process. You take our service for school, medical, company cab at http://www.btslimo.com

If you are going to Europe then it's a great idea to have a road trip since most of the European countries are connected by road. Last time when I was there, I found a good service, namely Routperfect, they were offering road trip Europe services on heavy discounts. You can checkout them as well now if the discounts are available these days.http://www.routeperfect.com/trip-planner/