Normal SD card Android development is slowing down after NAND Android and Windows Phone 7 came out. However, there is a way to run Android on SD card with NAND Android or Windows Phone 7 installed on your phone. It can be done with the help of SD MAGLDR Android ROM. Normal SD card Android cannot run on current MAGLDR without modification. However, most of the SD Android ROM chefs do not support it officially. And left only few that current still developing and supports it through SD MAGLDR method. Here are the top 3 SD MAGLDR Android ROMs that I tried based on CyanogenMod 7, HTC Desire Z and HTC Desire HD builds.
SD card Android is not finished yet. Thanks to several xda-developers like copenhagen. They are still making Android ROM for SD card. Copes CyanogenMod 7 SD MAGLDR Android ROM is one of them. It is based on Android 2.3.2 Gingerbread and using AmeriCanAndroid HK853+ Kernel. And good news ~ it is runnable on MAGLDR. Perfect combination with Windows Phone 7 (for those still use it).