While not officially supported, it is possible to have Adobe Flash on your Android 2.1 (Eclair) device.
You can do so by downloading and installing the package included in this post. Note that you will have to have third party applications allowance enabled so that you can install it. Possibly, on some devices, you have to install Apps Installer to install the package.
Flash player works, but because of missing components in 2.1, there are some performance issues.