Only you can decide whether to leave your computer on, or turn it off. There are reasons for each strategy. The typical computer draws around 100 Watts, or 2.4 kWh/day. Multiply this by your electricity rate per kWh to come up with the cost per day. Leaving a typical computer on all the time would cost about 21¢/day (2.4 kWh * 8.6¢/kWh). This may not seem like much but it adds up to close to $75/year. There are reasons to leave your computer running 24 hours per day. One is if you use it as a web server, or if you use it to receive faxes 24 hrs/day, for your at-home business. If these do not apply to your computer, then it makes sense to turn off your computer when it is not in use.

Fluorescent lighting technology has significantly improved in recent years. One such technology is called "electronic ballasts." Unlike older magnetic or transformer ballasts, electronic ballasts eliminate that annoying hum and flicker and allow the bulbs to emit light which is better quality. Instead of slowly getting brighter as they warm up, they turn on instantly.
Fluorescent bulbs are also available now that have better color. When purchasing bulbs there are two things to look for: the Color Rendering Index (CRI) and the Correlated Color Temperature (CCT). The CRI rates the ability of the bulb to render an object's true color when compared to sunlight. Look for lamps with a CRI of 80 or higher. The CCT refers to the color objects emit when heated to a certain temperature on the absolute temperature scale (Kelvin). The lower numbers correspond to reddish color and the higher to blue-white color. For color similar to incandescent lighting look for CCTs around 2700. Often, the warm, white fluorescent lamps are sold as "kitchen and bath" lamps.