Back in the 1870s, a newspaper editor named Christopher Latham Sholes rearranged the letters on typewriters so that the keys would stop jamming. The result was the QWERTY keyboard... and his innovation has actually fundamentally altered how we think about words.
That's the idea put forward by Kyle Jasmin of University College London and Daniel Casasanto of the New School for Social Research. The idea builds on a well-supported psychological phenomenon known as the fluency effect, which basically means that the harder a word or a name is to pronounce, the less positively a person will feel towards it. (Oh, so that's why I wasn't popular in high school. Always wondered about that one.)
Jasmin and Casasanto argue that QWERTY keyboards have provided a new way in which to organize letters, and with it a whole new way for us to find words easy or difficult to communicate. Specifically, they say that the left side of the keyboard is harder to deal with than the right. There's a few reason for this — people tend to be right-handed, there are more letters on the left side than the right, and the letter pairs that are toughest to type are found on the left side.
To test the hypothesis, the researchers showed a thousand words to English, Dutch, and Spanish speakers, and asked to rate how positive the meanings of the various words were. Even though the participants weren't typing out the words — so they were unlikely to be making any conscious connections with the keyboard layout — they tended to rate the words from the right side of the keyboard more positively than those from the left.
This effect even extended to made-up words, and there was no difference in the reactions of right-handed and left-handed participants, so it's likely a result of the disparity between the number of letters on each side of the keyboard. That said, though there is evidence of a correlation here, the researchers stress that they haven't demonstrated an actual causal relationship just yet, and it's likely that a word's actual meaning is still far more important in how a person feels about it.