>I have a table of warrants with latitude and longitude, and I would like to be able to select all warrants within a given radius. I know I've seen this discussed before. Any of you math professors got a clue?

hhmmmm, this calls for pythagoras...

lets say your on position xPos and Ypos and your the location is at xDest and YDest, and your radius is nRad, I'd go for the following solution

SELECT * FROM Warrants WHERE SQRT((xPos - xDest) ^ 2 + (Ypos - yDest) ^ 2) =< nRad

If its getting to slow you can think of adding additional for the benefit of rushmore like:

AND xdest BETWEEN xPos - nRad AND xPos + Rad AND yDest BETWEEN yPos - nRad AND yPos + nRad

of course you need indexes on xDest and yDest

Walter,