When Cnet tested cooling pads http://news.cnet.com/8301-17938_105-9700… out of the 8 they checked out, the one without any fans cooled the best http://reviews.cnet.com/docks-stands/xpa… the XPad.
In your case, you *might* want to consider having the unit actually taken apart periodically. Why? Are you familiar with how a clothes dryer works? You know the lint trap? You know how after one use, there is enough lint on that screen to form a layer thick enough to peel off in a single pull? Well... the fan in your laptop sits in front of a heat sink. That heat sink is a piece of copper or aluminum, cut so that there are parallel fins that the fan pushes air between. The leading edge of that heat sink catches debris over time... and the more debris that is caught, the more that *debris* catches even more debris, until you get a layer of material between the fan and the heat sink. This will obviously impede the flow of air in the cooling channel.
This happens to EVERY laptop... and it happens in as little as 2 months in some environmental conditions, and it can take 6 to 8 months to get really bad in other situations. So, I can't tell you how often it will happen to you. What I can say, is that if you have never had that cooling channel cleaned, and the unit is at least a year old, then there *IS* a layer of that dust/debris between the fan and the heat sink within your laptop.
Some laptops have a panel over the fan, where you can simply remove this panel and then you are able to service the fan easily. Other laptops require you to completely disassemble the unit to the point of removing the motherboard to get at the fan and heat sink assembly. I have no idea the make and model of your laptop, so I can't say whether it will be easy or not for you.
What I am saying though, is that before you try chill pads or clip-on fans... you might want to consider simply cleaning the laptop.
If you have get that so best wishes for you.