One thing that looks cool to me on a cruiser is a nice set of freeway bars. Not to mention that they protect the bike and with that in mind another nice piece of chrome does not hurt either. These things offer great protection against an accidental drop and keep your paint and frame from taking the hit. Its definetly easier and cheaper to replace freeway bars then what you would be out of pocket on having to repaint your rider or worse yet the frame. Also I think that the looks of the bike are improved with a nice set of chrome highway bars.
The other easy change would be some custom grips. You can find some really cool motorcycle grips these days that will accent your ride. Mirrors are another easy accessory that you can change. Kuryakyn makes some really cool mirrors with skulls or Maltese crosses as well as some that are just a nice piece of chrome.
A new air breather can also give your bike a custom look. lets also not forget a new set of pipes for a meaner growl.
There are a huge amount of cruiser accessories out there for you to choose from. It all boils down to a matter of personal taste and if you own one of the more popular brand bike you will find a crazy amount of aftermarket accessories to choose from to customize your cruiser to your tastes. If you have a custom bike or one that is not a one of the mainstream brands it can be hard to find accessories and you might have to make modifications to anything you buy or look in to a custom fabricator to make you anything you might want to add.
Check out our section on cruiser accessories we carry http://www.discount-motorcycle-parts.net/motorcycle-accessories-t-22.html