One of the features that I use the most in TextMate is the ability to jump between most recent used files using Cmd+T.
Here's how it works in TM: if you are editing file A and you do Cmd+T and select B.
Now when you are editing B and hit Cmd+T, it show a list with A first, then B, then the other files.
Let's say I pick C, it will now show B as the first option, then A and then C, followed by the other files.
This is a kind of Cmd+Tab for the editor.
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