MacOS – the normal fan speed for the 15” Retina Macbook Pro

I’ve used smcFanControl when I had a 1st Gen Macbook Pro 15’’. It’s not harmful in the sense that the fan is designed to be on, but of course, like any other mechanical device, the more you use it, the faster it wears out. If your Macbook Pro is getting too hot, try one of those utilities to see if it helps. In any case, getting a cooling pad is not a bad idea. Depending upon the type of work and conditions that you have, a Fanless may be enough.

I believe the “best” fanless was the iLap. And for cooling pads with a Fan, you’ll have to see and trust the power of Google Shop. These generally use a USB port to drive a couple of Fans. Among the best features you can look for are the provision of an extra USB (so you don’t lose your port), portability if you move and sound level of the fans, whether they can be turned on/off, etc.

I've used SpeedFan with Windows running in a Bootcamp partitions to access temperature data and control the fan speeds on an iMac. He's very quick to turn around unsupported chipsets and the software tells you if you should report your chipset to the author for addition.