h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Neither have arms, though both have legs

Both can be found in many kinds of wood

Also

Because at one time there lived a man by the name of Finneus Martin, and he was a brilliant carpenter. He roamed through the countryside searching for inspiration for his latest piece of fantastic furniture. One day as he was traipsing along through a wood he found himself alarmed by a raucous cry, he was so startled in fact that he tripped over his rather pointy shoe and fell flat on his nose. His assailant, he found, was a rather large and presumptuous raven. Now Finneus was a vengeful man, and so he vowed not to let the slight pass. That evening he went back to his work room and began fashioning a writing table the likes of which had never been seen. After a long night of toil and trouble (and presumably some boiling and bubbling as well, seeing as Finneus was rather fond of tea) the piece was finished. People came from all around to view the fantastical piece of furniture, and all agreed that it was a writing table, and it was also rather like an unsettlingly ugly raven.