#shell user
adb shell -t 'export HOME="/data/local/tmp";busybox sh'

#start as root
adb shell -t 'su -c "export HOME=/data/local/tmp;busybox sh"'

#aliases
alias adbsu="adb shell -t 'su -c \"export HOME=/data/local/tmp;busybox sh\"'"        
alias adbshell="adb shell -t 'export HOME=/data/local/tmp;busybox sh'"