Site Specific Browsers (SSBs) provide a great solution for your WebApp woes. Using Fluid, you can create SSBs to run each of your favorite WebApps as a separate desktop application. Fluid gives any WebApp a home on OS X desktop with Dock icon, menu bar.
"Are you a Gmail, Facebook, Campfire or Pandora fanatic? Do you have 20 or more browser tabs open at all times? Are you tired of some random site or Flash ad crashing your browser and causing you to lose your (say) Google Docs data in another tab?"