Useful Free Software

[Mystix]

If you're looking for a good free image compression utility, I could recommend Caesium : https://saerasoft.com/caesium/
I've been trying it out for a bit and it seems to do a nice job to reduce image file size while still usually keeping good visual quality, so could be good for getting your artwork images you might want to post on this site to a bit under the 1MB limit, or for resizing and compressing an profile Avatar image.
When using to compress images, I'd suggest to output to a different folder location, or to use a copy of the images you want to compress (otherwise the utility will overwrite the files selected to compress, but it should give a warning message about that).

[Mystix]

Some other good free software that I use;

GIMP image editor: https://www.gimp.org

IrfanView image viewer: https://www.irfanview.com

Image Glass - another image viewer, I like to use this one when I want to keep an image on top of other things, so for example when using an image as a reference: https://imageglass.org

Media Player Classic - still a great video player: https://mediaplayerclassic.org

Handbrake - This tends to be my go-to video compression utility: https://handbrake.fr

Edit Pad Lite - A good alternative to Windows Notepad and in some ways a lot better with more features: https://www.editpadlite.com

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Well, that's a few things I tend to use often. If you have some good free software you'd like to recommend, feel welcome to share here.

[RedAISkye]

Here's my recommendations:-

• Image Editor: Paint.NET
• Media Viewer/Editor/Convertor/Compressor: XNViewMP
• Image Reference Overlay: OnTopReplica
• Media Player: VLC
• Media Thumbnail/Cache Shell Extensions: Icaros
• Video Editor: VEGAS Pro (Pirated Copy)
• Video Compression: Handbrake
• Audio Editor/Converter: Audacity
• Text/Code Editor: Notepad++

[Mystix]

CPUID / CPU-Z - A utility for showing a computer's detailed system information: https://www.cpuid.com/softwares/cpu-z.html

Duck Station - A great Play Station 1 (PS1) emulator (you'll need to source a PS1 BIOS file, but it's easy enough to find): https://www.duckstation.org

PCSX2 - Play Station 2 (PS2) emulator: https://pcsx2.net

VICE - A good emulator for old Commodore computers (Vic-20, C64, etc..): https://vice-emu.sourceforge.io

OBS - Open Broadcaster Software: https://obsproject.com

Easy Cat Timer: https://easycattimer.com

qBitTorrent - My go to Torrent software: https://www.qbittorrent.org

[Mystix]

BES - Battle Encoder Shirasé. "BES is a small tool that throttles the CPU usage of the process you “target”". I find it can be quite useful in some cases to limit CPU usage, or be an 'anti-freeze', of some software that may tend to be too much of a hog or that perhaps may even cause a computer to slow-down or 'freeze': https://mion.yosei.fi/BES/

Process Lasso: Real-Time CPU Optimization and Automation (there's a Free version, though after trying it for a while I decided to get the Lifetime Pro version which has more features): https://bitsum.com/download-process-lasso/

CleanMem: "CleanMem keeps memory use in check on the system without the memory being pushed to the page file. This in turn keeps the system running smoother.".
I've been using this little utility for several years and I find it can make a difference in helping the computer to run smoother. The free version works fine and you can see how it works, though I got the Pro version which has some extra features:
https://www.majorgeeks.com/files/details/cleanmem.html

[DarkKuroi]

Besides XnView there is standalone free (for personal use) batch converter XnConvert https://www.xnview.com/en/xnconvert/
I'm using it everyday to convert all new images from pixiv and other places to 75% jpeg quality for storage and viewing purposes.

[RedAISkye]

Besides XnView there is standalone free (for personal use) batch converter XnConvert https://www.xnview.com/en/xnconvert/
I'm using it everyday to convert all new images from pixiv and other places to 75% jpeg quality for storage and viewing purposes.

Yeah, that is already built-in with XNView MP.