1. Turn off internet access. This one is pretty obvious, but it's not always practical if you are doing bibliographic searches, say, or downloading articles.
2. Xobni. I installed this a few months ago, and, if you use Outlook, it really is helpful for finding phone numbers and especially file attachments. It does more, too, like showing you when you typically get e-mails from those on your contact list.
3. Leechblock. This is the new and improved version of the Greasemonkey script that blocks certain web sites for specified periods of time; it's a Firefox add-on, and you don't need Greasemonkey to use it. You can tell it to block the sites for certain periods of time (7-5, for example), or set up a different set of rules to allow yourself X amount of minutes on certain sites. It's almost as good a timesaver as turning off the internet access.
4. [Edited to add] Eggtimer. This is still useful for doing "sprints" of writing. You lucky Mac people have a free version.
5. Music. The music CDs that Dr. Brazen Hussy suggested look good, but if you've already spent your stimulus check, there are alternatives.
- If you already have a lot of this classical music (Bach, Mozart, Schubert, Vivaldi, etc.) on CDs or in iTunes, you can group them in playlists so that they mimic the brain effects of the CDs (at least I hope this is true).
- Also in iTunes: try the Classical tab for radio stations. Good ones for working include the Adagio station, All Classic Baroque, WCPE, and even Whisperings, although the free version of the latter plays the same tracks over and over. Some of the public radio stations work well, too, although the big city ones tend to play "challenging" and modern--i.e., too noisy for work purposes--classical rather than the quiet stuff, and they interrupt the quiet music with opera at odd moments, a total distraction.
- Pandora, of course. Pandora has a lot of generic classical stations already set up (although Piano Solo, Romantic Period is heavy on Schubert), or you can create your own by specifying a composer.
- Local classical radio stations. These are good for times when the internet is off, although if your local station has jumped on the "challenging" bandwagon or prefers a lot of rousing marches, you're out of luck.