If you share webpages on Facebook using the “Share” link or a bookmarklet on your computer, you might not know that you can edit the URL and summary text seen in the window:
Just click on the URL or summary text (it will turn yellow as seen in the screencap above). You can then change either (or both) texts to read whatever you want. In the above example, I could change “Portable App Directory | PortableApps.com – Portable software for USB drives” into “Portable Apps” or even “Cool stuff!”.
Note that you can also delete the summary text (the paragraph under the yellow text in the screencap above) completely if you want to.