There are some great side tables out there that won't empty out your pockets. With a discerning eye and a little scavenging, you can find plenty of options for whichever design style you tend to swing towards. Here are two that I think have great lines and have enough character that they deserve a title more than just "sidekick".
This sweet number from West Elm is following the nature trend of the moment. At $179, the Branch Side table won't set your budget over the top and will add a whole lot of personality to your room.
If you are the classic type, you might be drawn to this Alchemy Side Table from CB2. With a nod to classic laboratory equipment and only $249, you can afford to do some additional design experimentation on the rest of your home.