- Open the Terminal
- Use wget to download http://airdownload.adobe.com/air/lin/download/1.5/AdobeAIRInstaller.bin
- Set the file to be executable: chmod +x AdobeAIRInstaller.bin
- Run it: sudo ./AdobeAIRInstaller.bin
- Accept any AIR updates
- Use wget to download Seesmic Desktop from http://d.seesmic.com/seesmic/SeesmicDesktop-0.2.1.air
- On the Ubuntu desktop, not terminal, look under Applications->Accessories or Applications->Other for Adobe AIR Application Installer and run it
- Select SeesmicDesktop-0.2.1.air and the normal Seesmic Desktop installer will run
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