Install Windows 7 without a DVD drive
Is it possible to do a fresh install? I only have a hard drive and windows 7 ISO file.
Got a USB port? Can you boot off of it? Have a 4GB flash drive handy? How about a system you can prepare the flash drive on with .NET Framework 2.0 or higher? If so, you probably want the Windows 7 USB/DVD Download Tool. You might find this tutorial handy.
Update: Fixed links.
Assuming you have a host PC running Windows 7 or Vista you can make the USB key bootable using DISKPART. I wrote up some fairly detailed instructions on my website to install Windows 7 on an Acer Revo.