The first of a few Piriform programs on this list, CCleaner—the first C is for Crap!—is one of the best, and pretty much essential for keeping a system going. What it does is simple: it cleans up extraneous files to keep a system running better. Get it and run it, regularly. It'll even delete some apps you didn't think you could get rid of—like those provided in Windows 10, whether you wanted them or not.
Ready to install a whole metric butt-load (that's a thing) of programs for Windows all at once, like after you purchase a new PC? Don't grab them all individually—visit Ninite first and check off all the programs you want. You can then download a custom installer that will place all the programs on the PC in one massive installation session. A huge number of the products on this list are available right there.
Got a slew of CBR and CBZ files laying around on your hard drive unread? These compressed files full of scanned-in comic book page images are easy to read with the right software. The right software is ComicRack, because it does a lot more than just display the images—it'll even share the files across your network, and provides full database organization of the comics. Use the Windows version to sync comics to the mobile apps.
Many people new to free software find themselves confused because the word "free" in the term "free software" is not used the way they expect. To them free means "at no cost". An English dictionary lists almost twenty different meanings for "free". Only one of them is "at no cost". The rest refer to liberty and lack of constraint. When we speak of Free Software, we mean freedom, not price.
This last point, which allows the software to be sold for money seems to go against the whole idea of free software. It is actually one of its strengths. Since the license allows free redistribution, once one person gets a copy they can distribute it themselves. They can even try to sell it. In practice, it costs essentially no money to make electronic copies of software. Supply and demand will keep the cost down. If it is convenient for a large piece of software or an aggregate of software to be distributed by some media, such as CD, the vendor is free to charge what they like. If the profit margin is too high, however, new vendors will enter the market and competition will drive the price down. As a result, you can buy a Debian release on several CDs for just a few USD.