A hard thing for a creator to shake is being accused of ripping off someone else's creation. It's even more terrible when there are similarities, but they are completely unintentional and coincidental. And then one finds himself having to explain this, knowing full well those who are inclined to dislike him are much happier presuming the worst (or most probably, will never read this at all).
In Original Life, I had Stacy suffer a night of torment to break her addiction to nicotine, and I fell back on the creative stand-by of personifying the object of her addiction as a projection of her mind. It's actually a very common thing to do. Someone trying to overcome an alcohol addiction would be tempted by a talking whisky bottle, or the feminine charms of a bottle of wine. I remember one Kids in the Hall sketch where a fellow was trying to overcome his addiction to tea. In his feverish nighttime torment, David Foley was chasing him around the house dressed as a gigantic tea bag, seductively murmuring alluring and vaguely sexual enticements. In any event, my depiction of an anthropomorphic cigarette drew comparisons to the "Mr. Butts" character in Doonesbury. It blindsided me because I don't follow Doonesbury and I'm not familiar with its characters. The few Doonesbury comics I've read in the past didn't lead me to believe I'd enjoy it further, so I never thought about it again. But nonetheless, my depiction of an unnamed, one-shot, anthropomorphic cigarette drew some accusations that I'd "ripped off" Doonesbury. At least one friendly person noticed a similarity, and then I noticed one rabble-rousing Twitter child making the accusation of a rip-off. I can say it's a very terrible thing to draw up something that appears for two pages, only to learn that someone else's creation has a similar concept from many years ago.
Here are some links so you can see.
http://jaynaylor.com/originallife/archives/2012/04/304.html (the OL page with the unnamed mental figment of a talking cigarette)
http://en.wikipedia.org/wiki/Mr._Butts (A wikipedia entry about the Doonesbury character, with illustration)
Probably the real irony is that I DID do an intentional homage to Bloom County in the very same story arc, when I had Stacy clutching a knife in her jaws while she was tied to a chair. I was pleased at the people who got the reference from that one page. But there were no accusations of ripping someone off. I guess that's the difference between an entire plot arc and a character that just kinda looks like another character. Plus, I imagine the kinds of people who'd enjoy a comic like Doonesbury are the same sort of rabble inclined to presume the worst about me and sling an accusation right out of the gate. The kinds of people who like Bloom County just have better taste and manners. Makes sense.