With Locale and the Wake On LAN Plug-in (WOL), your phone can wake up a sleeping computer when you are in a specific situation, for example entering Work.
Your computer needs to be configured to be able to wake up.
Requires the free app “Locale” from the Market.
AEP-Emu (DE/EN)
DMG Page (DE)
Indie Retro News (EN)
Retroguru (EN)