DXF is a very popular CAD file format which has been around since 1982, so you might expect there to be plenty of good viewers around by now.

Unfortunately, the reality is very different. DXF can be complex, and while there are free viewers to be found, they're generally of not much use.

Whether you're concerned about security, or just hoping to optimize your PC’s performance, understanding what's accessing your internet connection can be very helpful.

Network monitors will tell you more, but they're often targeted at experts, weighed down with complex details which -- even if you understand them entirely -- you may not really need. GlassWire is an interesting free network monitor aimed at a more general audience. It’s easy to use, looks great and provides in-depth reports, but they’re easy to follow and focus on only the most important information.

Resizing and repositioning windows on the PC desktop is such a fundamental task that you’ll almost do it without thinking. Move the mouse to the title bar/ border, click, drag, release. Very basic, very simple -- but there might still be room for improvement.

KDE Mover-Sizer is an open source, portable tool which brings a common Linux desktop trick to Windows. Instead of having to move your mouse cursor to the title bar or border, you just hold down the Alt key, then left-click anywhere inside a window and drag to move it, right-click and drag to resize it.

SMART (Self-Monitoring, Analysis and Reporting Technology) is a monitoring system which reports on various reliability indicators, and sometimes highlights imminent hardware failure of HDDs and SSDs.

These predictions can sometimes be questionable, but SMART still has plenty to offer, and the open source HDD Guardian (also available in a portable edition) provides a simple and straightforward way to find out more.

Popular system optimization tool CCleaner has been updated to version 4.17 with a series of mostly browser-related improvements.

The official release notes say the new build -- also available in a portable version -- adds "Google Chrome and Opera GPU cache cleaning". We’re not entirely sure what that involves, but it’s here anyway: let’s see if it makes a difference.

YEd Graph Editor is an interesting free diagram designer with some unusual features.

The core interface works much like many similar applications. You’ll choose your symbols from a palette (flowchart, UML, ERD, BPNM, network, computer, more), drag and drop whatever you need onto the page, and position them as you like. Symbols may then be customized with text, colors, URLs and more, before you join them up with lines to represent your structure or ideas.

Shape Collage is a photo collage tool with a difference. You're not restricted to creating collages with the standard rectangle or "pile of photos" look: they can use whatever shape you like.

The free-for-personal-use program crams a lot of functionality into a single window, but smart interface design means it's still very easy to use. Click the "Add" button, choose a few photos (local, from your online accounts or a general internet search), click "Create" and that's it: your first collage.

Argente Utilities is a one-stop PC maintenance suite with tools to clean, optimize, repair and generally improve your system's speed and reliability.

It's a relatively lightweight, portable package, arriving as a 7.5MB zip file, and there's no adware or similar hassles: just a gentle "donate" screen which you can dismiss forever with a click.

MultiHasher is a very well-designed file hash calculator which comes packed with essential features and functionality.

The good news starts with the download. It’s free, a compact 2.75MB and entirely portable, just unzip and run.

John Haller’s PortableApps.com has announced the release of PortableApps.com Platform 12, a major update for the all-in-one app manager.

Right-clicking the Platform system tray icon now displays a cascading menu containing all your apps, links to system folders, Backup/ Restore/ Eject functions and more.

PhotoWand is a free photo effects app for Windows 8. It’s not going to compete with the desktop equivalents any time soon, but there’s more than enough power here to make it genuinely useful.

There are simple and practical tools to improve your photos, for instance, including a crop function, blur and sharpen filters, and adjustments for hue, saturation, brightness and contrast.

There are thousands of image viewers available for Windows, and the chances are you already have more than you need. Does the free Honeyview have anything to make it worth a download? Let’s see.

One immediate plus is that the program comes from Bandisoft, developer of the excellent free archiver Bandizip, and a firm that knows exactly what it's doing.

The average selfie can look a little strange, oddly framed and at a weird angle as you strain to fit everybody in. Usually no-one cares -- it’s supposed to be spontaneous, that’s that point -- but sometimes you just can’t get any kind of picture, no matter what you try.

Snap Clap is a simple Android app which helps out by taking a photo when you clap your hands.

Antivirus software installations are often complex, involving many low-level alterations to your PC and its settings. Sometimes they don’t work as they should -- or the regular uninstaller fails to remove them completely -- and this can leave you with all kinds of frustrating problems and system instabilities.

Security vendors often have stand-alone tools to properly remove and clean up after their products. A quick web search should point you in the right direction, but if you’re regularly cleaning up other people’s PCs then the free Antivirus Remover could save you a little time.

eBooks come in many different formats, and while some are easy to read anywhere (PDF, DOCX) others can be much trickier to handle outside of your regular reader (FB2, PDB). If that’s a problem, you might like to try TEBookConverter, a portable tool for Windows which converts these more awkward eBooks into something you can access just about anywhere.

The program is essentially a shell for Calibre, which immediately gives it support for 25+ common formats: djvu, docx, epub, fb2, html, mobi, pdf and more.