Inkjet printers can clog or jam when the ink dries somewhere inside the printer.  Where and how much ink dries inside the printer determines how bad the 
inkjet will jam.  Worse, most inkjet printers clean themselves by <b>sucking</b> large quantities of ink all at once out of the printer cartridge.  To add 
insult to injury, not only is your inkjet printer jammed, but it might take 2 or 3 of those $25 ink cartridges to clear the jam... until it jams again.  
<p> 
The basic advice is to try to 1) reseat the ink cartridges (take them out, bang 'em on the table or sink, put 'em back in) 2) clean to printer with 
denatured alcohol 3) clean the printer with windex.  Unplug the power from the back of the printer first unless you want to jam your central nervous system 
too. 
<p> 
A color laser printer circumvents all this BS.  Color lasers are under $1000 now, and the toner costs about the same as the money you'd waste on 
try to unjam your inkjet with the cleaning function.  Most web pages on unjamming inkjets focus on problems with Epson, but are Cannon and HP inkjets really 
that much more reliable?  If the design was so rock solid, why are there entire websites of abstract, vague advice on how to care for and unjam them?
<p> 
Here are some web pages where other have down experiments with unjamming their own inkjet 
printers (read very carefully as the following is not expert advice): 
<ul> 
<li> <a href="http://eddiem.com/photo/printer/unclog/unclog.html"> Unclogging EPSON inkjet heads </a> 
<li> <a href=""http://www.inkjetart.com/tips/cleaning.html"> Some suggestions for unclogging your Epson printer </a>
<li> <a href="http://www.hardwaresecrets.com/article/178">How to Unclog Epson Print Heads </a>
<li> <a href="http://www.maxpatchink.com/prev-maint.shtml">Preventitive Maintenance for Inkjet Printers </a>
<li> <a href="http://www.imaging-resource.com/ARTS/CLOG/CLOG.HTM"> Surviving a Clogged Cartridge </a>
<li> <a href="http://www.weeno.com/art/0899/140.html"> How to Clean Clogged Inkjet Printheads </a>
<li> <a href="http://www.inkmagic.com/epson_clogged_printhead.htm>  How to clean Epson Printhead Nozzles which are Blocked or Clogged. </a>
<li> <a href-"http://www.lockergnome.com/nexus/windows/2006/04/26/how-to-clear-a-stubborn-inkjet-printer-clog/"> How To Clear A Stubborn Inkjet Printer Clog
</a>
<li> <a href="http://www.rottentomatoes.com/m/office_space/"> Skeet Shooting For Dummies: If All Else Fails </a>
</ul>
Don't thank me.  Thank Carly Fiorina.  Way to stick it to the man, lady.