For those visual learners in the group, here's a chart to help convert from decimal to binary.

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| 256 | 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
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| | | | | | | | | |
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The values in the top row are powers of 2 taken out to the eigth power, which is as far as you'll need to go to work with IPv4 IP addresses. If you have to go further than that, may God have mercy on your soul.

In the binary numbering system, the only digits you use are 0 and 1. So, to use this chart you'll take your decimal number, say, 150. 150 is smaller than 256, so you put a 0 in the 256 place. Then you move on to the next column. 150 is bigger than 128, so you put a 1 in the 128 place and you subtract 128 from 150, which equals 22. 22 is smaller than 64 and 32, so you put zeros in those columns. 22 is bigger than 16, so you put a 1 in the 16 column and subtract 16 from 22, which equals 6. 6 is smaller than 8 so you put a 0 in the eight column. 6 is bigger than 4 so you put a 1 in the 4 column and subract 4 from 6, which equals 2. 2 equals 2, so you put a 1 in the 2 column and subtract 2 from 2, which equals 0, which means you're done. You then put a 0 in the 1 column, because you didn't use it. The resulting chart looks like this:

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| 256 | 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
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| 0 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 0 |
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The resulting number in binary is 010010110.

The E2 Offline Scratchpad rocks for making charts :)