I read an interesting DailyWTF post today, \"Out of All The Possible Answers...\" and it interested me enough to dig up the original forum post where it was submitted. This
The LCM of one or more numbers is the product of all of the distinct prime factors in all of the numbers, each prime to the power of the max of all the powers to which that prime appears in the numbers one is taking the LCM of.
Say 900 = 2^3 * 3^2 * 5^2, 26460 = 2^2 * 3^3 * 5^1 * 7^2. The max power of 2 is 3, the max power of 3 is 3, the max power of 5 is 1, the max power of 7 is 2, and the max power of any higher prime is 0. So the LCM is: 264600 = 2^3 * 3^3 * 5^2 * 7^2.