I just found out that some shareware I'd bought a few years ago has officially been made free. As it happens to be the single-most useful utility I've ever used, I just emailed all my friends and suggested they try it. That got me thinking that a) it might be worth mentioning here, and b) it would make a good opportunity to mention other programs, and hear from everyone on the little things that make their computing life better.
So here's a list of things that save me time, starting with the one that's now freeware. NOTE: I'm a Windows user; I doubt any of these exist for the Mac OS (sorry!).
FileBox Extender http://www.hyperionics.com/files/index.asp
-- It gives you access to a list your favourite folders (and recently used ones, too) in EVERY Open and Save dialog box (popup). I have folders for all kinds of work stuff, several photo and music folders, downloads, etc.; so when I save, say, an email attachment from one of my clients, just one click and I'm ready to save it in that client's folder -- no more constant navigating to My Computer or wherever.
-- It makes those Open and Save dialog boxes much bigger, actually using the space available on your monitor -- so there's far less scrolling or resizing of the window to see all your files.
Agent Ransack/FileLocator Pro http://www.mythicsoft.com
Agent Ransack (free) and FileLocator Pro ($30) allow you to search for text within files. It lists the matching files on the left; when you click on one of those results, it shows you the relevant line of code on the right (along with the line number), letting you decide whether it's really the file you're looking for or not.
Agent Ransack is very useful; FileLocator Pro, which I just purchased, is even more so (and worth it).
Lupas Rename 2000 http://rename.lupasfreeware.org
A fantastic and powerful file-renaming utility. Lots of filters and options. Great for changing "DSC104233.jpg" and "IMG003993.jpg" to "Paris vacation 01.jpg" and "Paris vacation 02.jpg".
Cobian Backup http://www.cobian.se
A powerful and free backup utility. It can backup via FTP to a website, or backup the files from the website (even raw mysql files), it zips, it can even run any task you want before it starts the backup (I have a little image that pops up reminding me to save certain files before it starts its backup). Small system footprint.
Allway Sync http://www.allwaysync.com
A free tool to sync files between folders or drives. When I researched the quality of free syncing utilities, this one seemed the best, and it has worked quite well.
There are a few other utilities I use that are more system-related, but the ones above are probably more relevant to this forum.