If you're trying to install Windows 7 on a netbook (or are having issues with your PC's optical drive), the free USB Download Tool from Microsoft allows you to take a .ISO image and turn it into a bootable flash drive.
This was created not only for netbook users, but for anyone that opted to download Windows 7 from Microsoft in lieu of ordering an installation DVD. Windows 7 USB Download Tool can create a bootable flash drive (or DVD, if you prefer) from the downloaded .ISO file in quick fashion—just install it and follow the on-screen prompts. Note that if you opt to use a flash drive, it must be 4GB or larger to hold all the files.
The coolest part: Microsoft has open sourced this little app. Why, you ask? They got a bit of flak early on in the project for re-using open-source code and improperly documenting it (as well as making the program itself closed source), but true to their word that it was only a mistake, it's been brought back and declared open source for all to use. So if you still haven't gotten Windows 7 installed on that netbook of yours, head on over to CodePlex, Microsoft's open-source repository, and download the tool now.
Windows 7 USB/DVD Download Tool [via Download Squad]