Accessories are not only important to everyday style, but also to workout clothing. Look for special holders for your water and/or iPod. Many of these holders are quite fashionable and can be found in a variety of designs, colors and styles.
Having both of these things readily available during your workout or activity decreases the need to stop in the middle of your session.
Also, look for fun and funky ponytail holders for your hair and matching sweatbands for your head and arms. Fingerless gloves provide protection for your hands during weightlifting and give you a retro edge to your style.