Why Write an Emulator in Visual Basic? 
There are a few reasons for this. 
Firstly, I'd always wanted a Space Invaders Screen Saver, so I had to make one myself. VBEmu was the first step in achieving this goal. 
Secondly, when I started this project, I didn't have enough experience in C++ nor did I own a copy of C++. 
Thirdly, it had to have a pretty front end. This is quite easy with Visual Basic. 

Isn't Visual Basic too Slow? 
Yes! When Visual Basic compiles its source, the code which is generated is not very well optimised and there is very little you can do to speed things up. The approach that I had to take was to use a external CPU library. A 'C' version was very kindly produced by Larry Bank, author of the very impressive CAGE windows based arcade emulator (see the 'Links' section for more details) and he is currently working on his 32-bit 'asm' version of this library. Using this technique, VBEmu can run at full FPS on a Intel P133 system with sound enabled. 

How Easy is it to Write an Emulator in Visual Basic 
To cut a long story short, I've made the source code freely available for download. Have a look yourself if your at all interested (its quite well documentated, I think!). 

Is the Screen Saver Available too? 
Yes, you'll find the link above. 

Is There Plans for More Games to be Supported 
At the moment, no. Though you can never tell in football. 
 
Is there anything else I should know? 
Read the online 'Help' file if you get into any trouble.