If you have been installing custom ROMS for a while, its likely you will have a few Nandroid backups stored on the Sdcard. While its possible to extract these files on on a desktop , accessing the contents on the actual device is made simple using the Nandroid Browser app.
Install the app as normal , run and it will display all your current backups. Click on one to view the contents, and you will then see each part of the backup eg ‘boot.img’ , ‘system.img’ etc.
Clicking on these allows you to extract and install individual apks , great for saving time. You can even extract any photos or videos which are contained in the recovery and then email or save them to your current ROM.