MenuPrefs

MenuPrefs allows you to check your system preferences easily. It does this by putting the main categories of System Preferences in a drop-down list on your menubar.

The menubar is always up there, so if you want to go to your Energy Saving preferences, you can simply click on the appropriate button, and the system preferences window for that category will be opened. This will save you a couple of clicks and a few seconds each time you have to access system preferences.

By default, the categories are listed in plain text, but from the preferences window, you can add icons to the categories, which might help you find them on the list more easily. You can also customize the size of these icons with a small bar. I found that the small icons work best, since they don't take up much space and they look nice. MenuPrefs seems to also let you customize the elements on this list, but I couldn't get that feature to work.

MenuPrefs wasn't always free, but it is now. You will be asked for a registration code, which is on the developer's website. All you need to do is copy and paste it onto the window and you will successfully register the app. It won't bother you with nag screens after that is done.