How can I keep recent files from appearing in Unity?

Method 1: Using Activity Log Manager

Ubuntu Precise 12.04

In Ubuntu Precise Activity Log Manager 0.9 is included by default. It can be accessed from System Settings or just by looking for Privacy.

Or you can simply type Privacy in Dash

Now you can start blacklisting applications. Screenshots

Activity Log Manager in Oneiric and first release

You can install Activity Log Manager from the Stable PPA.

For more details about Activity Log Manager you should check out the article on OMG! Ubuntu! and article on Webupd8

A new version of Activity Log Manager is in development which looks better and is simpler to use. A screenshot of the unreleased Activity Log Manager

Method 2: Using Gnome Activity Journal

You can do it, provided that there is some pattern in the files. For example you have kept all your explicit content in folder /home/mrpig/erotica/ folder.

Then open Activity Journal which is a GUI frontend to Zeitgeist which acts as a Dashboard showing your recent activities. On top right Zeitgeist Icon, click it and Preferences. Check "Blacklist Manager" plugin

Then goto "BlackList Manager" tab. Click on New button, and then edit the new entry which comes as file:///home/mrpig/erotica/*

Linked Question:

1. Hidden files are shown in Dash

There is a way to do it, but it will clear all the other recent files as well.

All you have to do is run the following commands:

rm ~/.local/share/zeitgeist/activity.sqlite
zeitgeist-daemon --replace

Edit zeitgiest/activity.sqlite no longer exists on my system:

rm ~/.local/share/zeitgeist
zeitgeist-daemon --replace

It takes a moment, but it repopulates as the daemon starts.

Update: Activity Log Manager has been released. This is a GUI tool that allows you to tweak the Zeitgeist history: you can delete part of the Zeitgeist history, blacklist some applications or prevent logging certain types of files as well as blacklist folders.

Install it using the commands below:

sudo add-apt-repository ppa:zeitgeist/ppa
sudo apt-get update
sudo apt-get upgrade
zeitgeist-daemon --replace
sudo apt-get install activity-log-manager

I've recorded a video demoing Activity Log Manager here: http://www.youtube.com/watch?v=-eQn7ZyfSlw

Just rename the folder after browsing. After you renamed it, the files in there won't show up in unity recent files. Pretty easy solution, just make sure you don't forget it every time you use that folder :)

(Sry for my english)

The old "making .recently-used.xbel a folder" trick does work, but now the file is in ~/.local/share so:

$ rm ~/.local/share/recently-used.xbel
$ mkdir ~/.local/share/recently-used.xbel

...works for me :)