The software listed below is completely free, is completely legal, and I use each of them personally. The list below is constantly updated as I find new useful software and is aimed at Windows users.
AOMEI Backupper Standard
Can be used to backup individual files and folders, but also to backup partitions and complete disks as well as clone partitions and disks. Also has an option to create a boot CD to deploy backup images to bare metal in case of disaster recovery. Scheduling backups with e-mail notifications are supported as well.
Macrium Reflect Free
Alternative to AOMEI Backupper. The free version has more limitations than AOMEI Backupper Standard; File and Folder backup and e-mail notifications are not included in the free version.
Acronis True Image
Acronis True Image is perhaps the gold standard in imaging software but Acronis themselves do not offer a free version of the software. There are however, special ‘lite’ versions with stripped down functionality that are specially created for hard drive manufacturers Western Digital and Seagate. As long as you have a hard drive by one of those companies installed on your system (internal or external), you can use this ‘lite’ version of Acronis True Image for FREE.
In case you own a Western Digital hard drive: http://support.wdc.com/product/downloaddetail.asp?swid=119
In case you own a Seagate hard drive: http://www.seagate.com/gb/en/support/downloads/discwizard/
If you are unsure what kind of hard drive brand you’ve installed in your computer, you can download Speccy to find out: http://www.piriform.com/speccy/download/standard
SyncToy synchronizes files and folders between locations. Typical uses include sharing files, such as photos, with other computers and creating backup copies of files and folders.
Anti-Malware / Anti-ADware / Anti-Spyware Software
In case of a malware/adware/spyware infection, always start off with a MalwareBytes full system scan, then proceed to scan with the tools listed below
AdwCleaner is searches for and deletes Adware, Toolbars, Potentially Unwanted Programs (PUP), and browser Hijackers from your computer
RogueKiller can find/remove most of the basic malwares (rogues, trojans, …) and some advanced threats like ZeroAccess or TDSS that behave more like rootkits, based on generic ways to find malwares by their behaviour (heuristics) and on classic anti-malware analysis (signature finding)
CCleaner is a free Registry and junk-clearing utility for keeping your system clean and optimized.
(Protip: Have CCleaner automatically clean your PC when it boots, so you don’t forget to do so yourself!)
MiniTool Partition Wizard Home Edition
MiniTool Partition Wizard Home Edition is a comprehensive disk partition manager and includes features as Merge Partition, Move/Resize Partition, Copy Partition, Create Partition, Split Partition, Delete Partition, Format Partition, and Convert File System.
Installs and Updates All Your Programs at Once. It says “No” to toolbars or other junk, always installs the latest version of an app, installs the right 32-bit or 64-bit version for a PC, installs apps in the PC’s language, skips apps that are already up-to-date and upgrades an app if it’s out of date
WirelessKeyView recovers all wireless network security keys/passwords (WEP/WPA) stored in your computer
Mail PassView is a small password-recovery tool that reveals the passwords and other account details for all major e-mail clients
ProduKey is a small utility that displays the ProductID and the CD-Key of Microsoft Office (Microsoft Office 2003, Microsoft Office 2007), Windows (Including Windows 7 and Windows Vista), Exchange Server, and SQL Server installed on your computer.
WebBrowserPassView is a password recovery tool that reveals the passwords stored by all major web browsers
Acronis Drive Monitor
Acronis Drive Monitor is a free tool that helps monitor your hard drive, and prevent data loss.
Excellent tool if you’re wondering what’s eating up your diskspace. WinDirStat is a disk usage statistics viewer and cleanup tool.
Alternative to WinDirStat. TreeSize Free shows the size of a folder including all subfolders and files. In an Explorer-like style, also the wasted space
StarWind RAM Disk
One of the fastest RAM Disk Emulators I’ve used.
H2testw is a free tool that can be used to test for Counterfeit or Fake USB flash drives, and check your USB Flash Drive for errors. It works by filling the chosen target drive with test data and then reads this data back to verify it.
eM client is a fully featured e-mail client that supports all major services including Gmail, Exchange, iCloud and Outlook.com
VSO Image Resizer
Great tool to resize multiple pictures to be able to send them by email, for example. Just right click to easily resize pictures. Also includes advanced options such as watermarking etc.
Ashampoo Burning Studio Free
Great alternative to Nero Burning Rom with an intuitive GUI.
Notepad++ is a source code editor and Notepad replacement that supports several coding languages.
(Protip: Also download the ‘Compare’ Plugin using the built-in Plugin Manager)
A torrent client that does just that: Download torrents. No bloatware, no unnecessary features. Great alternative to uTorrent or qBittorrent.
An alternative to Microsoft’s Remote Desktop Connection (RDP). Doesn’t require any port forwarding and will work behind most, if not all, company firewalls as it uses port 80. Great tool for remote support purposes.
7-Zip is an excellent alternative to WinRAR/WinZip and can (un)pack just about any archive format
The Combined Community Codec Pack is a simple playback pack for Windows with the goal of supporting the majority of video formats in use today. CCCP is an excellent alternative to the bloated and outdated K-Lite Codec Packs
The best free webbased eBay sniping tool!