Install Devel::Trace (libdevel-trace-perl in Ubuntu) and launch your program using "perl -d:Trace ./xx.pl" like syntax. This gives you tracing similar to "set -x" on shell scripts.
Until recently rtorrent didn't support adding new trackers to torrent except by editing actual .torrent. Either manually, with some tool or via online service such as http://www.torrenteditor.com. Recently support to add trackers on the fly to active torrent was added, but documentation seems to be little thin.
"Usual" places on Linux will show wrong CPU frequency for Intel Turbo Boost enabled CPUs. You can check actual frequency used with "i7z". It works with i3, i5 and i7 series processors.
Been bit quiet lately. I might as well document another hack to entertain my very small audience. This time post is about how to add custom entries to Windows 7 start menu. Not under all programs, but directly to same level as other options such as Control Panel, My Computer etc.