Darktable Open Source RAW Darkroom

I've just become a fan of this amazing piece of software. Just everything about it seems to be perfect. The noise reduction is stunningly good while preserving details. The sharpener brings out crips details down to the single pixel. You may even be able to tether you camera via USB and control your camera's settings and shooting with live view directly from your computer. It even does some tone mapping, imports GPS data into your photos and more. I was going to say now it only has to take the photos itselt. But with tethering, in a way, it already does. :)

Simply fascinating. Try it out!

Hints: Check out some tutorials if you get stuck.

Quickly Shrinking the File Size of a PDF File on the Command Line in Linux

Ok, I'm most linking to a great page here. But I'll also give you my favorite choice: GhostScript, which is available almost on every system and did a terrific job in my test:

gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen -dNOPAUSE -dQUIET -dBATCH -sOutputFile=output.pdf input.pdf

Of course it also takes other formats like ps and eps or jpg as input!