The wonderful add-on for Firefox, DownThemAll is great for times when you want to save an entire website worth of pictures, movies, or documents, but you don't want to save each one individually.
To accomplish this, we utilize the under appriciated "Links" panel and Opera's nifty "Save to Download Folder".
Notes:
1. Be sure you know where your download folder is! Generally it's under C:\users\[username]\Downloads for Vista and "My Documents" in XP.
2. The steps below were run on the 32-bit version of Opera 9.6 for Windows Vista but should work for every platform and Opera version since at least 8.0
This part should be easy. Go to your favorite porn site/web site/whatever site and find a list of filetypes you can "right click > Save As..." Here, I've found some strangely identical renderings of Ferraris. Sure, let's grab em.
Take a look at the tooltip that pops up on the set of files you wish to download. I've circled the paris-speak that we will later use to uniquely identify this particular set of files
Now that you know what it is you want to download, find a way to narrow it down using Opera's quick find feature in the Links panel. Note the tooltip you get when hovering over a link and look for something that is unique enough to narrow the results. In this case, the crazy paris talk should be unique enough to drill down the entire set of identically posed Ferraris: "ecran".
Word of advice though, the links panel is focus sensitive... meaning if you switch to a new tab, the links panel will follow and your downloads will stop if they were not completed! Simply hit the "Lock" button before moving tabs and you're golden.