Today I Learned...

Apache

Configure Postfix to only send emails
Find a file's MIME type

Command Line Tools

Convert videos with avconv

Debugging

Output a nicely formatted stacktrace in PHP

Drupal

Create a URL to login as any user (Drush)

Git

Search Past Git Commits for String

Linux

Analyze disk space usage
Check Swap Usage
Find out how many times an IP shows up in apache logs
Map disk on linux to VMware (vSphere) SCSI
Recursively list files by last modified date
Show installed perl modules

MySQL

Dump and Restore Large DBs without large performance hits
Remote Dump Database
Identify locked tables and unlock them
Monitor running queries

PHP

One-liner: Import CSV

VIM

Autocomplete with VIM
Batch Format Files in a Directory
Close All Splits But Current
NERDTree File Management