This command provides more color variety for the rainbow-like appearance by generating random color codes from 16 to 231 for adb logcat.
adb logcat|awk '{ i srand();for (i = 1; i <= NF; i++) { color = int(rand() * 216) + 16; printf "\033[38;5;%dm%s\033[0m ", color, $i;} printf "\n"; }'