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Forum Moderators: martinibuster
I would suggest you refer back to Google and Yahoo!'s webmaster guidelines.. they both suggest you ask yourself "does this benefit my end user's experience?"
So to answer your question, if the "off topic" link benefits your end user because there is some information there to be learned about your widget, then get the link.
Don't worry about this too much.. if the vast majority of your links are definitely on topic, then one or two slightly irrelevant or off topic links won't hurt you.
What hurts is HIGH VOLUME IRRELEVANT link development. Avoid high volume irrelevant link exchange and you will do just fine.