Colored noises
white noise, pink noise, brown noise
Sounds of Nature
Beach, Crickets, Forest, River, Rain and Storm, Whales, Heartbeat
Household sounds
AC, Shower, Vacuum cleaner, Fireplace, Clock, Washing machine
Travel
Car ride, Airplane, Train
Lullabies
Twinkle Twinkle, Warm Kitty, Brahms's Lullaby