Tails can be installed to a USB Flash drive, and can be booted from an ISO file on a multiboot USB boot drive if you use the cheat code 'findiso' which luckily Tails supports. See this post from Ilko which shows how the findiso cheat code can be used. A tested and working grub4dos menu.lst entry from that post is shown below (as the post is poorly formatted!):

Once you create your Tails boot disc, you'll be ready to reboot your computer from a USB drive into an encrypted and private operating system preloaded with all the software you'll need to browse the Web, email, IM, and edit documents.

• Built-in online anonymity: The key feature that's going to appeal to most people is Tails' built-in online anonymity. This comes in the form of the customized web browser Iceweasel built using the anonymous Web browsing technology from Tor. The browser also includes popular security extensions like HTTPS Everywhere for secure browsing, Adblock Plus to block ads, and NoScript to block Java and Flash. Other than those features, the web browser works exactly like you'd expect a web browser to work.
• Built-in encrypted email and chat: Additionally, you also get encrypted and private messaging. Tails includes the Claws email client with OpenPGP for email encryption and the instant messaging client Pidgin with an OTR cryptography tool that encrypts your IM conversations.
• Built-in file encryption: When boot Tails from a USB drive instead of a DVD, you can save documents to the thumb drive and they're automatically encrypted using an encryption specification called LUKS. (Since the DVD is read-only, you can't save any files - which is its own form of security.)
• A full suite of editing software: On top your web access being private you also get a full suite of work and creative software. Tails comes preloaded with Openoffice for editing documents, Gimp for editing photos, Audacity for editing sound, and lots more additional software

You can use the menu below to boot Tails from a USB Flash drive or USB Hard Disk.

Note: If booting from a USB hard disk, you must remove the live-media=removable cheat code (this forces Tails to only look at removable drives when loading the 2nd stage filesystem)!

This also applies if you are booting from a USB Flash drive using a Virtual machine - the VM will treat the USB Flash drive as a Fixed Disk and Tails will not boot if you have live-media=removable set.

Tails does not support persistence on the boot drive for security reasons.

title Start tails-i386-0.15 LIVE (persistent)

#http://dl.amnesia.boum.org/tails/stable/tails-i386-0.15/tails-i386-0.15.iso

#add a casper-rw ext2 file to your USB drive using RMPrepUSB Create ext2 FS button for persistence

set ISO=/tails-i386-0.15.iso

ls %ISO% > nul || find --set-root --devices=hf %ISO%

map %ISO% (0xff) || map --mem %ISO% (0xff) || map --mem --heads=0 --sectors-per-track=0 %ISO% (0xff)

map --hook

root (0xff)

#note kernel line below is one long line followed by one initrd line

kernel /live/vmlinuz findiso=%ISO% boot=live config live-media=removable noprompt timezone=Etc/UTC block.events_dfl_poll_msecs=1000 splash nox11autologin module=Tails quiet splash

initrd /live/initrd.img

root (bd)

You can add both the XP and Vista/7 tables to the same \tables folder and thus be able to crack Windows XP/Vista/7 passwords.

You can download more tables and put each set of tables in its own directory under \tables (its name is not important, all folders under \tables will be searched):

tables\vista_free
tables\vista_special
tables\XP_special

WARNING: 2014 version does not support USB 3.0 or exFAT. Use a USB 2.0 port (even if using a USB 3.0 drive in a USB 2.0 port). FAT32 and NTFS is OK.

Note: if you do extract the \tables folder from the ISO file, you can simply delete the large \tables folder from the ISO using a suitable ISO editing tool like ISO Maker or Daemon Tools Pro.

Better still, use the small ISO ophcrack-notables-livecd-3.6.0.iso and download the tables separately.

Booting Ophcrack from an ISO without extracting the \tables folder

mkdir /media/oph

mount /dev/sdb4 /media/oph

Note: This example assumes that your USB device will be the second disk in your system (i.e. the system has just one internal hard disk, sda, and no other external drives connected), if you have several drives connected, you may need to specify sdc4 or sdd4 rather than sdb4.

...try this procedure if you are not sure what device the 4th partition of the USB drive has been detected as by linux...

First click on My Documents folder on Desktop and then click on the drive symbol for your USB drive - if you have clicked on the correct USB drive, it should immediately change it's name to SliTaz ophcrack and you should be able to see a tables and boot folders within it, then in a console window, now type ...

mkdir /media/oph

mount

(look at what \dev\sdx4 device is mounted as /media/SliTaz ophcrack - e.g. it could be /dev/sdb4). The entry should always end in 4 as it is the fourth partition.
In the Explorer GUI window, right-click on the SliTaz ophcrack device and choose Unmount File System to unmount it. Now mount it to sdb4 by typing...

mount /dev/sdb4 /media/oph

title Load xbmcbuntu-12.00-RC1.Intel-NVIDIA.iso

debug off

# set the path and filename on this next line

set ISO=/_ISO/Linux/xbmcbuntu-12.00-RC1.Intel-NVIDIA.iso

# make empty table entry in 4th position in ptn table

parttype (hd0,3) | set check=

set check=%check:~-5,4%

if "%check%"=="0x00" partnew (hd0,3) 0 0 0

if not "%check%"=="0x00" echo ERROR: PTN TABLE ENTRY 4 IS ALREADY IN USE! && pause && configfile /menu.lst

# map the iso file to a partition

ls %ISO% > nul && partnew (hd0,3) 0x00 %ISO% > nul

debug 1

map %ISO% (0xff)

echo -e \r\n

map --hook

root (0xff)

kernel /casper/vmlinuz boot=casper live-media-path=/casper nopersistent quiet splash --

initrd /casper/initrd.lz

This method also works with BackTrack 5 ISO files (but persistence does not work).