Reading from the keyboard without blocking under EventMachine is pretty simple. Just use the builtin EM.open_keyboard and give it a connection handler. If you want to use Readline as well, unfortunately, you'll block the reactor unless you change the behavior of $stdin.
Connect to Pry remotely using EventMachine with tab-completion, paging, user authentication and SSL support.
GNU Screen is a great terminal multiplexer or simple window manager for CLI interfaces. Newer versions support spliting a single terminal window both horizontally and vertically. Whenever you detach from a Screen session, any split windows you setup in that session will be lost unless you run nested Screen sessions.
Use net-ssh within EventMachine without blocking the reactor.
Back In Time is a great GUI that reproduces the most important OSX Time Machine features: simple graphical configuration and snapshot backups. The current version (0.9.26) is, unfortunately, broken if you want to back up an entire installation. There is a fix, but the developer has not released it yet. Applying the fix yourself is, fortunately, very easy.
The only variable is the number of sectors. Calculate it by (size in MB) * 2048
Last week I recorded 190+ medical engline terminology audio flashcards for Yoshiko and her classmates at Nihon University School of Medicine. They figured that it would be a lot easier to remember the words if they could hear a native speaker pronounce the words and phrases whenever they wanted. That's fine, but I wanted to know when they downloaded the MP3s.
Using a Content Delivery Network will cut down on your hosting fees and improve user experience. Most CDNs are expensive. Building your own is horribly expensive and complicated. Google is cheap and easy, but in a good way.
From the very start KanjiTastic has given you a quick way to retrieve kanji that look similar to the one that you are studying. All you have to do is click on the “Related Cards” link at the top of the card then select Similar Kanji.