Apple has released iMac SMC Firmware Update 1.1, which is recommended for recently released iMac models that have been configured with PCIe-based flash storage (see “Apple Updates iMac with Faster CPUs and 802.11ac Wi-Fi,” 24 September 2013). The release improves the Power Nap feature in OS X 10.9 Mavericks so that it runs silently while your iMac is sleeping without spinning the fan. (Free update, 921 KB)
Enabling Auto Spelling Correction in Snow Leopard
In Snow Leopard, the automatic spelling correction in applications is not usually activated by default. To turn it on, make sure the cursor's insertion point is somewhere where text can be entered, and either choose Edit > Spelling and Grammar > Correct Spelling Automatically or, if the Edit menu's submenu doesn't have what you need, Control-click where you're typing and choose Spelling and Grammar > Correct Spelling Automatically from the contextual menu that appears. The latter approach is particularly likely to be necessary in Safari and other WebKit-based applications, like Mailplane.