iStat Menus 2.0 is in final beta phase, and should be released to the public soon. It's quite an improvement over the previous versions, and is 10.6 compatible.
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iMac 27" 3.4GHz Core i7, 20GB RAM, 256GB SSD, 1TB HDD • 27" LED Cinema Display
MacBook Pro 13" 2.8GHz Core i7, 16GB RAM, 120GB SSD
iPhone 5 32GB • iPad 2 WiFi + 3G 64GB
Mac mini 2.3GHz Core i5, 16GB RAM, 128GB SSD (XBMC)
Synology DS1512+ NAS • DX513 Expansion • 20TB