I have a Mac computer which I really like. I had a Mac PPC which I bought in March 2006, just 3 months before they came out with the Intel chip Mac Pro. Yeah, bad timing since they stopped the PPC at OS-X 10.5, Leopard and many applications companies, including Adobe, dropped PPC version in 2009.
So in December 2010 I replaced it what the last generation Mac Pro, and the same thing now, yeah bad timing, since Apple has released the rumor they may drop the Mac Pro line next year or thereafter. But it's a rumor as they've also hinted they may retrofit the newest generation of chips for them so they don't have to develop a new Mac Pro around them.
This solves two issues, keeping the Mac Pro line alive along with all of the dedicated users, as it's the workhorse of many professionals in many fields, mostly the arts, designers, scientists, etc., who need highend power and speed (processors) and maximum capabilities (4 HD slots with tons of input/output connections). Things an iMac just can't do easily, if at all.
Anyway, since I've started mine, I've become a menu bar junkie. You have to be careful with the applications on the Apple App Store as many aren't even worth the $1-5 price, and especially the free ones. The ratings have value, so read and use caution. I always visit the developer's Website to see what they say there for details and additional information.
Anyway, while I've wasted a few bucks here and there, I've found a bunch which are quite good and handy. That said, I'm running 21 menu bar apps after the normal system preferences which you can display on the menu bar. And pray tell, what do I like? Ok, here's the list, from right to left.
Earth Desk - Buy this from the Website and not the App Store.
DataColor's Spyder 3 - For monitor calibration with their hardware.
Caffeine - Great to keep the window turned on (screen saver).
XMenu - The best for launching applications with custom lists.
Pathfinder - Better than Apple's Finder in most cases.
My IP Address - Handy when you want to know.
Cookie - Great little cookie, flash cookie and database manager.
Smart Report - Monitors SATA HD's.
Simon Monitor - The free version works for 5 Websites.
Tiny Alarm - Great little tool.
Notes Tab - Good for quick notes.
Calendar Bar - Ok if you want just the iCal display.
Twitter - The obvious Twitter interface.
FaceBook Menu Tab - Ditto for FB.
Radium Radio - Great for getting all Internet stations.
MailUnread - Nice Mail interface.
AirFoil - Great tool to send audio from any app to one or more outputs.
CoverSutra - Nice iTunes interface.
NowPlaying - Nice for displaying iTunes song information.
Visits - Good, easy to read Google Analytics interface.
Cursor Coordinates - I keep losing where the cursor is and this tells me.
Weatherman - Probably the best menu bar weather tool.
Anyway, that's my menu bar. The first I'd recommend to get for your Mac is Caffeine to keep the monitor on without changing your system preference settings. The second is a monitor color calibration tool. The third is if you listen to the radio, then get Radium Radio. After that, it's just personal choices and your pocketbook.