"Beaver Cleaver used to say ``reckon'' all the time, and he was hardly a Southern figure."
"Well, sh*t far and slap the dog!"
Irregardless, Beaver Cleaver was a bit before my time but Southern Slang was the first thought that entered my head. I guess it's obvious that I don't read the dictionary on a regular basis because in fact I reckon it's a real word, but yes that was my first thought when I heard the word; kinda brought me back a few years. Ahh yes high school.... I'll never forget phrases like "Dem taters is GOOD!" or "Ya'll had enuff sure enuff?"