Useful software add-ons for MacOS 10.6

This list is by far not complete and unordered, but more a mere reminder to myself and for interested people and will be updated (thanks to a friend who had always a tip handy, as soon as I ran into problems during changing from the Windows to the MacOS world - see his Mac Blog - I also stick to many of his suggestions, which I will not always repeat here)

• ever sat in a (boring) talk and wanted to start up your MacBook? Of course, when you shut it down last time, you forgot to silence the sound, so the nice Apple "baaahm" is well audible for the whole auditorium. Very embarrassing indeed... the solution is StartupSound.PrefPane - free software where you can set the initial volume at startup to always be muted.
• for playing almost any movie, there is Perian
• if you have more than one digital camera or an iPod/iPhone and you don't want to have iPhoto startet every time you connect them, use Cameras for managing them.
• for internet browsing I stick to Firefox
• my favourite email-client is Thunderbird
• TinkerTool allows the nerdy heart to change preferences, show hidden files in the Finder and so on. Actually, it does NOT add any features, it simply makes built-in options which are normally hidden from the user available in a Mac-like fashion
• for tracking my bank accounts, I use Pecunia, an open-source HCBI (PIN/TAN) banking software - which is still under development and tries to become a complete private financial software.
• For typing LaTeX documents, I use both TeXShop and TeXWorks. TeXShop is the plain one, which I also use for Lilypond (a TeX-like sheet music typesetter), TeXWorks is a little more sophisticated with a preview-pane.
• If you need to put formulas in e.g. Keynote presentations, there is this very nice piece of software called LaTeXit.
• I use OpenOffice as a free replacement for Microsoft Office, although one has to live with minor conversion issues. 
• Dropbox  as replacement for an USB stick with automatic versioning and synchronizing of different machines.