Install busybox on HTC Desire with Android 2.2

android-install-busybox

Connect HTC Desire via USB cable.
Make sure USB debugging is enabled.

$ cd /path/to/android/sdk/tools
$ adb push busybox /sdcard/busybox
$ adb reboot recovery

The phone should restart in recovery mode.

$ adb shell
device># mount /sdcard
device># mount -o rw -t yaffs2 /dev/block/mtdblock3 /system
device># dd if=/sdcard/busybox of=/system/bin/busybox
device># chmod 4755 /system/bin/busybox
device># mkdir /data/busybox
device># /system/bin/busybox --install -s /system/bin/
device># reboot