I really like CM7 and am a daily user. But I also really like HTC Sense and like to use Myns Warm TwoPointTwo RLS5. Is there any way I can dual boot so when the phone starts up, I have a choice to which ROM I can use? That would be cool, any help would be appreciated, Thanks.
I believe that there is no such mod out there (don't take my word for it).
I believe that this is possible but it would require alot of patience since ROMS like myn and cm7 are not bootable from the SD and require installation into the phone's built in
memory. This would require the program to backup-delete-install the specific rom every time you want to boot into another rom (sounds confusing?) since it needs to save all the recent changes and etc.
The closest thing we have today is nandroiding between ROM backups. It only takes about 5min or so to restore a nandroid backup. Not sure if what you are wanting is possible or not, so it will be interesting to see the responses you get. I'm sure if someone developed such a thing people would be willing to pay for it!
There is a project on XDA where a member is working on this exact thing. You will be able to flash a ROM to your built-in memory and also to a partition of your SD card. Its been in the works for quite a while so I hope it is completed soon!