Pentatonic scales are significant in almost every musical tradition, but in some they play a more central role than others. No clearer example of this springs to mind than Japanese music, which is based on pentatonic scales with just a few auxiliary tones.
Traditional Japanese music uses basically two types of scales. Both are essentially pentatonic but one makes uses of auxiliary notes while the other confines itself to five. The first has three modes used interchangeably, the second is relegated to sacred music and has male mode: ryu, and a female mode: ritsu. And they have attached to each of the five tones, five elemental natures: fire, metal, wood, water, and earth.
These scales sound exotic to western ears and are interesting anyway, but the fact that they work so well when played with western motifs makes them really exciting territory for adventurous players. Adding the occasional riff in a Japanese scale can really add a whole new dimension to a solo.
These scales are fairly easy to remember as the patterns they make on the fret board are always the same, just in different combinations. Here are two different Japanese scales from the same position, both with A as the root note:
These scales are also very similar to pentatonic scales used in Indonesia and other parts of Asia, making them very versatile if applied well. Once you get the scale down, just playing straight through a couple of times is bound to jumpstart your creative mind; there are so many really cool ways to sneak in this sort of sound, and it definitely makes a welcome break to the same old blues riffs.