Well, I'm sure lots of us who have !# installed, also have multiple OSes (in GRBU list). And I've always hated the fact that if I was in Linux and wanted to boot windows, then I'd have to reboot, wait for grub to show, and then press the down arrow. Well GRUB has an awesome way to reboot your computer with a Onetime only selection of an alternate default listing.
First thing that must be done is to edit your menu.lst file
open it up in gedit with the command
gksudo gedit /boot/grub/menu.lst
near the top of your document look for
# You can specify 'saved' instead of a number. In this case, the default entry
# is the entry saved with the command 'savedefault'.
# WARNING: If you are using dmraid do not use 'savedefault' or your
# array will desync and will not let you boot your system.
#default 0
You may or may not have a # infront of the default, refardless you want to change it to look like
# array will desync and will not let you boot your system.
default saved
Don't close Gedit just yet, now scroll down and look for
## ## End Default Options ##
We are going to add saveddefault 0 after each menu option
Your entries should look somewhat like this
...
title Ubuntu 8.10, kernel 2.6.27-7-generic
uuid BUNCH-OF-RANDOM-CHARS-NUMS
kernel /boot/vmlinuz-2.6.27-7-generic root=UUID=BUNCH-OF-RANDOM-CHARS-NUMS ro quiet splash
initrd /boot/initrd.img-2.6.27-7-generic
quiet
savedefault 0
title Ubuntu 8.10, kernel 2.6.27-7-generic (recovery mode)
uuid BUNCH-OF-RANDOM-CHARS-NUMS
kernel /boot/vmlinuz-2.6.27-7-generic root=UUID=BUNCH-OF-RANDOM-CHARS-NUMS ro single
initrd /boot/initrd.img-2.6.27-7-generic
savedefault 0
title Ubuntu 8.10, memtest86+
uuid BUNCH-OF-RANDOM-CHARS-NUMS
kernel /boot/memtest86+.bin
quiet
savedefault 0
...
WINDOWS/Other Linux stuff will be further down here
Now you can save the file and close.
Now that we've enabled the entries to use a default saved, you can try out my improved openbox-logout script.
There are 2 methods that it can be executed.
Both Methods Start Here:
Download this file... and save it to the default location
http://www.mediafire.com/?gdjst4nxccl
Open a terminal (Super + t) and type in the following
chmod +x ~/Desktop/openbox-logout && cp ~/Desktop/openbox-logout ./
Then, we will execute this new logout script (just to see if you like it)
First Method Here (Otherwise SKIP to Second Method):
you should have a window popup that looks like so

Now you won't see the Boot Into... window until you click the Reboot Into... Button. What it does when you click that button is, reads your GRUB menu.lst and populates the combo box with all your Legitimate GRUB boot options. Then you can choose what OS you want to boot into on the next reboot, and click OK. Effective method for those advanced users with Lots of OSes installed.
Second Method (my favorite):
Because I only have one other OS on my machine next to !#, I'd prefer not having to select it from a combobox every time, I'd rather just a custom button. Well I built that into the script as well. Follow these simple instructions.
Open a terminal if not already open, and then type
gedit ~/.config/CrunchBang/grub-boot-once
and here is what I write in my file
The first line in the file is the name of the OS you want, you can put whatever you want there.
The second line in the file is the Index that it appears in the grub menu.lst. It so happens that 0-2 are always the defualt (!#, !# (recovery mode) and !# memory test). Then the 3rd option happens to be just a place holder "Other Operating Systems" and so the 4th index is my actual Windows Vista. Yours may be different, or the same, so adjust your number accordingly.
Now we are done with that, save the file and close gedit.
then run the command
and you should have something similar to

Conclusion and comments:
You may be alerted the fact that a gksudo window pops up asking for root priviledges, however this is one unfortunate side effect of the openbox-logout executing the command gksudo grub-set-default <index>.
Of course you can look at the python code in the openbox-logout and verity that I'm not doing anything malicious.
LASTLY... I Like it, how can I make it the default openbox-logout (so when I press Super Space, and go exit it runs your script)?
Simple, enter this command below
gksudo mv /usr/bin/openbox-logout /usr/bin/openbox-logout-old && gksudo cp ~/openbox-logout /usr/bin/ && gksudo chown root:root /usr/bin/openbox-logout
DONE!, now you can easily reboot to specific OSes.
Hope you like it!