One thing you can do with your plugin is this.
Ever hear of software directories submission? This is where someone builds a piece of freeware and submits it to software download sites. These sites will link to your site,and they carry huge PR and pass serious link juice.
When you build software, you build a submission document. This is an industry standard specification sheet for software submissions.
As the builder of a particular software, you can submit the software to the various download directories. They will approve or disapprove the software. Do not try to bullshit these people, they caught on decades ago to the value of their links and they are vigorous about defending their reputation for quality. Your software must work, and it must be yours.
PAY PARTICULAR ATTENTION TO THE NEXT SENTENCE
You can do this with any software that you have the rights to give away but you must re brand the software so it is yours.
This means you can create hundreds of backlinks from high PR high authority domains every time you submit a piece of software if you do it right. Fuck it up and you're a spammer and they won't approve anything you submit.
I do this service for my customers for $350.00 - $1200.00 depending on the directories I post their software to. I even got accepted to CNET so I can add software there. If you do it right, you get a permanent boost to your rankings.
For instance. say I have a car dealership i am doing this for. I buy giveaway rights to a car loan calculator software, rebrand it for the merchant, and upload it to the download directories. They get a gradual influx of very high PR links that ramps up as the directories approve their software. These links are in the company name and the link is related to car loans (or whatever). These links look very natural, because they are, and they stick like super glue. I mean for years, as long as you update the software details regularly. People who search for your customer will even find the software, and the credibility a consumer gives a software publisher is phenomenal. You must be pretty successful at what to do to distribute your own software free to the public in their eyes. Your client will LOVE you for this.
It's not simple to do this, and I make a good living out of it, so that is all I am giving you. You techies will figure it out, the rest of you will have to hire one of us, I guess.
Sorry to make you work for it, but if I gave it to you on a silver platter the half-wits will spam-fuck it up for everybody.
If you make a plugin for sale, put a lite version on these sites with a buy now button, and in addition to the links, more people will buy your software.