Surprise from the SkyBack in the day, every year when it came time for sorority rush, we used to cover the ceilings of our sorority's entryway, living rooms and den with curled ribbon. I have always wanted an excuse to mimic this decor, because cheesy as it may sound, there is nothing like curled ribbon hanging from the ceiling to shout "CELEBRATION!"
I finally got my chance to do it up ribbon-crazy this past New Year's Eve, but I think that this idea would work just as well for birthday celebrations (just use bright colors or primary colors instead of the black, white and silver).
If you really want to go all out: in addition to hanging the actual ribbon, you could also hang other theme-related decor from fishing wire or clear thread. For an example, for the New Year's Eve theme you could hang cut outs of stars, or for an under the sea themed party, consider hanging decorative fish from the sea of blue ribbon (I don't have kids yet, so you may have to wait another 7 or more years till I get to take this baby out for a spin), or for a butterfly or garden themed party, you could go with butterflies (small or large) amongst pastel curled ribbons (or shades of green would work equally as well).
The one downside is that the process can be a bit time consuming. However, if you are pressed for time, you can always choose to decorate one prominent area, like the area above a dining room table or the area above a cake or buffet table. The positive side is that you do get a lot of bang for your buck, and let's face it...after the party is over, all that hard work will pay off when you won't have to curl ribbon for presents ever again!
Ribbon Table Runner:Instead of using a traditional fabric runner, embrace the festivities, and create your very own table runner made out of curled ribbons. Simply curl long strands of ribbon in your choice of colors, and gather and shape in the middle of your table until you have achieved the shape of a runner.
To take this party decoration a step further, consider strewing additional decor on the runner. For a New Year's Eve celebration, add tea light candles (in proper candle holders, because ribbon catching on fire is never a good thing) or add some colorful New Year's Eve horns into the mix.
For a cake table, instead of making a runner, you could use a small round table and shape the ribbon to the size of the table top, and then place the cake on top of the ribbon. The same could be done for a buffet table.