Went out a few days ago to start my 85 tintop Vanagon; ugh...  No start, no click, no nuthin, but lots of red lights on dash.  Radio played; headlights turned on.  I have GoWesty auxiliary relay for house battery (a Walmart group 41 purchased about 6 years ago)...and it strained also..the reassuring "click" of switching to main battery was slow in coming.  And, I listened to my fuel pump; normally 2 strong pulses of fuel pump before engine ignites.  Not this time.  Instead, it groaned.

Got out voltmeter.  Only 11.37 VDC (Harbor Freight freebie voltmeter) across terminals.  Internet research says battery is dead.
Got out my records....well....it's been 12 years on my Kragen (now O'Reilleys) group 41 battery.  Yeah...I've been meaning to change it!  You know how it goes.
Went to Walmart for a group 41.  New price is about $100, old price 12 years ago was about $60.
Anyway, put it in.  Started right up, all systems GO.
I drive about 5,000 miles a year in my beloved Vanagon (second vehicle); it's in my garage in San Diego, so pretty mild weather conditions.  Still, I'm thinking 12 years is amazing.  

BTW....no corrosion noticed on terminals.  Good climate here.

Just FYI for you guys...I know you replace your starter battery before you are stranded, right?  (Oh, I guess if I was stranded I could have jumper cabled house battery to starter battery).  But, after 12 years, I figured the starter battery had given more than anybody could expect; very pleased.

RichSan Diego