ClipSafari is a free online resource for clip art. It has thousands of images, free to use at any time. Most people don't realize that you can't just use any image you find on the internet without crediting it or paying for it. This site makes it easy to find free images.
ClipSafari continues the mission of the Open Clipart Project. Open Clipart was an incredible resource for the community until it went offline. Thankfully, because the clipart on the site was licensed under a liberal public license, they have been able to legally reconstruct much of the content.
All images are available as PNG files and as high quality SVG files which look beautiful at any size. All clip art images are distributed under the CC0 "No Rights Reserved" license. You can copy, modify, and distribute these images, even for commercial purposes, all without asking permission.
Here is an example when I searched for "tech"
Take a look.