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How to make VB EXEs under 5K

This article will give you some tips and tools to squeeze those big 16/20/32K executables that VB makes when you only use one or two functions and get them to sizes as low as 1.48K.

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Getting the most out of your EXE files
We all know that VB makes very big EXE files, even if you only 
add an empty module. I think the minimum size you can normally get from VB is 
12K. Add a form, and that will usually go up to 16K. 
Before starting to use the tools I will mention, there are 
some basic tricks you can do. (Note that this assumes you are working on a very 
small VB application, not a fully-fledged product). 
Deoptimizing your code for speed
Firstly, since we are aiming for size, try to 
remove code like Variable1 = API Call Variable2 = API call(Variable1) 
Variable3 = TrimNull(Variable2) and replace it with a single line of code TrimNull(API 
Call(API Call)). Try to remove as many variables as you can from your code.

Another trick is that VB saves your project name in the 
executable, sometimes more then once, as well as your module/form's name. You 
can make the file even smaller by renaming your project and components to only 
one character. 
Finally, the last big code optimisation you can do (and this 
helps speed too) is to replace aliases by the real API name. Use ShellExecuteA 
instead of ShellExecute Alias "ShellExecuteA". Even better, if you are 
developping only for your computer or a single OS (XP for example), replace the 
API Name by their Ordinal Value. An Ordinal is a number that represents the 
location of the API inside a DLL. You can use the "Depends" tool that comes with 
VB6 to find the ordinals of each function. Then, just use "ShellExecuteA Lib 
"user32" Alias "#xxx" where XXX is the ordinal of ShellExecuteA. This will also 
make your code much faster, and much smaller. 
The last trick of course, is to compile in P-Code, as once 
again, we don't care about speed. 
However, you will probably notice that even after applying 
these optimisations, your file still has the same size. That is because VB uses 
a very large alignment (the space between sections within an exectuable) and 
your file will be padded with NULLs to reach 12K, no matter what. This is where 
it gets a bit more complicated. 
Packers
Your first choice is to use a packer called FSG (look for FSG 
1.33 packer on google). The packer will make your file around 3K. 
Or, you can use CompileController, from this site (Note that 
the code was "borrowed" from VBPJ by the author) and specifiy /FILEALIGN:0x200 
during the linking process. This will make VB create a pure EXE file, but around 
5-6K, instead of a file that will run in memory (as FSG). Save yourself the 
trouble, and just use FSG instead. It is much better then UPX by the way. 

Deleting ressources
However, you might still want to squeeze more out of your 
application's size. I promised 1-2K, not 3K as FSG probably did. Well, after 
compiling your executable, open it with "Resource Hacker" (google it) and delete 
all the ressources inside (Version Info and Icons). Don't save it just yet, as 
packers cannot compress ressource-empty files. The trick here is to create a 
1byte file (with notepad) and save it somewhere. Then, still in Resource Hacker, 
go to the Action Menu, and select Add New Ressource. Select the file you just 
made, and use type 3, name 1. Your file will now have a 1-byte dummy icon. Save 
it. 
The 12K executable might now be 11K, or 10.5, or might still 
stay at 12K because of the padding, but don't worry, FSG will see the 
difference. Use it on the ressource-empty file, and you should reach 2K. 

Of course, once again, this article assumed you are making 
some small helper application for your main app. It will have no icon, have 
unoptimized coding practices, and, depending on which API technique you used, 
will only work on a single OS. However, if that is what you are looking for, 
this article will help you squish those big nasty 16K files. As final trick, try 
using API code instead of Forms/Controls. Look for Viktor E.'s great code 
examples.
I hope everyone had at least something to learn from this!