Forget RAM, CPU, etc. The most cost effective way to speed up your Mac is with an SSD

Someone asked me the other day about upgrading to a new laptop.  Specifically they wanted to grab a new MacBook Pro (non-retina) to upgrade from their 2011 MacBook Pro which seemed to be getting slower for them.  Applications loaded slower, startup seemed to take forever, etc.  As I am a current user of a 2011 MacBook Pro, I was a little confused as to what they meant by slower since my machine is still very snappy for a 2 year old machine.  When I showed them what I meant by cold booting my machine from off to login screen in less than 15 seconds, they were floored.  Even when their machine was brand new, it never booted that quickly.  Opening up applications was even faster.  The difference between our machines?  I have an SSD and they have the stock 5400RPM hard drive.  My recommendation to them was to keep their still pristine looking laptop and simply swap out the hard drive for an SSD.  The one I run in my MacBook is a Crucial M4 512GB.  They're relatively cheap - Amazon has this particular model for less than $400 - and it truly is like upgrading to a brand new MacBook.  It's no wonder Apple is starting to move all of their products over to SSD. 

The great thing about the non-retina MacBooks is that it's still relatively easy to do upgrades yourself.  Check out the tutorial from the iFixIt guys.  Remember to back up all of your data before doing any hard drive swap out.  To me, CPU and RAM upgrades haven't provided nearly the same punch as going from a standard hard drive to SSD.  Once you've experienced it, you'll never go back and you can keep that old trusty laptop even longer before needing to upgrade.