For Umlaute to work in rxvt-unicode (urxvt) with zsh I had to add "export LC_CTYPE=en_US.UTF-8" to my .zshrc file and reconfigure locales to a default (en_US.UTF-8 rather than having none as default) with the "dpkg-reconfigure locales" command.

You may be running out of disk space fast if you have small SSD start partition on OS X Lion if you leave MobileBackups enabled.
If you open Terminal and run the command "df -h" you might see the (otherwise hidden) directory .MobileBackups using up a lot of space.

This feature is described in the Ars Technica OS X Lion review for example. It is there so your laptop will run backups even when you're on the move with no backup disk attached.

To disable it, run the command "tmutil disablelocal" in Terminal.
To enable it, use "sudo tmutil enablelocal"

This MacBook (black 2 GHZ Intel Core Duo) would not accept the firmware password I just set via the Firmware Password Utility from the Recovery Partition in OS X Lion 10.7.2.

The following steps let me turn off the firmware password protection. It only works if you haven't forgotten the password you had set. I my case this means I had used the correct password but it wasn't accepted. Seems like a bug, maybe specific to my particular (and rather old) hardware.

1. Open Terminal and type diskutil list
2. Mount the Apple_Boot Recovery HD partition with diskutil mount disk0s3 (use the identifier you see listed)
3. In Terminal type: open /Volumes/Recovery\ HD/com.apple.recovery.boot/BaseSystem.dmg
4. In Terminal type: open /Volumes/Mac\ OS\ X\ Base\ System/Applications/Utilities/Firmware\ Password\ Utility.app
5. Now you can turn off firmware password - again, provided you know the password you had set

Create a directory, move your files into it, issue this command from terminal:
hdiutil create -encryption -stdinpass -srcfolder mysecretfiles mysectretfiles.dmg 

Delete the unencrypted directory you created to start with.

OS X seems to cache ssh-key passwords by default. This is rather useless. You can disable this with
launchctl unload /System/Library/LaunchAgents/org.openbsd.ssh-agent.plist

Source: http://www.reddit.com/r/apple/comments/9fnnc/ask_rapple_how_do_i_disable_sshagent/

If you launch Keychain Access (in /Applications/Utilities/), and remove the entry for your ssh keys, you should be prompted for your password, and have the option to not save it.

To ~remove ssh-agent you can could run..

launchctl unload /System/Library/LaunchAgents/org.openbsd.ssh-agent.plist

..or use http://lingon.sourceforge.net/

Or unset the SSH_AUTH_SOCK env variable

Or, look at the ssh-add command - ssh-add -D forgets all identities (including removing relevant entries from Keychain), ssh-agent -t 123 sets it to remember identities for 123 seconds

If Apache won't start in your vserver, giving this error: Address already in use: make_sock: could not bind to port:80 make sure you don't have Apache running on your host system.

Two Wordpress sites are now live: mouthwateringrecords.com & stridenight.com. Both based on the excellent Structure Theme by Organic Themes.

To add a second google calendar on an iPhone where you already set up your first google calendar just visit this url from the browser (safari) on your iphone: http://www.google.com/calendar/iphoneselect

We're sponsoring our friends Doraine and Arne with a little website to support their fantastic work. Truly the funniest theatre company we know :-) Pay them a visit online, but most of all go see their shows! www.actiontheatre.ch

As crazy and esoteric it may seem, syncing your Apple AddressBook to Google really only works when your Mac is synchronized with an iPod or an iPhone. Just plugging such a device and syncing with iTunes triggers the sync to Google. You can also edit a file on your Mac instead to get the same result, as describe on Lifehacker.com:
Change the "Family ID." value to 10001 in ~/Library/Preferences/com.apple.iPod.plist

Thank you Gina Trappani and Josua Ferris!