In the event that you want to quickly send a link to Instapaper for a later viewing, you can do so with a new free jailbreak tweak called Actapaper by iOS developer Julian Weiss (insanji).
As shown above, you will be able to copy a link to your ClipBoard and then invoke and Activator action that you pick in order to send the link to Instapaper. At the time that you perform the Activator action, whatever you have saved in your ClipBoard will be sent to Instapaper.
You will get confirmation that your link is being sent to Instapaper after you perform the Activator action, and then you will get confirmation when the link has successfully been sent to Instapaper.
When it finishes, you can log into Instapaper and you will find the link that you sent there:
The tweak adds a preferences pane to the Settings application where you can log into your Instapaper account and choose an Activator action for Actapaper:
If you would like to give the tweak a try, you can download it for free in Cydia's BigBoss repository. You do need to have an Instapaper account, but you don't have to own the Instapaper application from the App Store ($3.99). Anything you save to Instapaper is easily viewable from a Web browser on your computer.