Air Sharing
Software vendor Avatron claims that 10 percent of all iPhone users have downloaded its $7 . If you aren't one of them, you should be: Air Sharing lets you mount your iPhone or iPod touch as if it were a wireless thumb drive, accessible from any Mac, Windows, or Linux computer. Let's say you're headed to a meeting. Before you go, you drag and drop files onto your iPhone. At the meeting, to share one of your files, you activate Air Sharing's built-in file server (which works over a local wireless network); your iPhone can then be mounted like any other network volume. Air Sharing handles scads of document types (including Microsoft Office, iWork, and PDF) and offers extensive built-in help.
Jaadu VNC
If you've used Leopard's screen-sharing feature or Back to My Mac, you'll get what's so cool about Jugaari's $25 : it gives you screen control over any computer (Mac or PC) that has Virtual Network Computing (VNC) enabled. You can use Jaadu VNC to control any application from your phone--you could, for example, run Keynote or PowerPoint presentations using your iPhone as a clicker. The program includes a rich set of combo keystrokes, so you can do almost anything from your iPhone that you could from your computer keyboard.
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