Graphics & Multimedia
Doing graphics in Visual Basic using the Windows API or OpenGL.
DirectX is a high-level API to access low-level graphics functions. Most modern video cards have drivers that support DirectX, making it easier to write applications with heavy graphics.
The MP3 music compression format represents a lot of interesting challenges for eager developers. Who hasn't thought of indexing their mp3 files and store the result in a database? :)
[>] Edanmo's VB Page
This site is all about advanced source code.

The source code itself is outstanding -- VB source for custom controls you have dreamed about and system operations you've wanted to perform. On top of that, you get a bunch of free pre-compiled controls and time saving type libraries ready for use.

[>] FreeVBCode
This site is a large and well sorted collection of source code. The code pieces range from banal to excellent, and should satisfy all levels of expertise.
[>] Hardcore Visual Basic
[>] Microsoft multimedia samples
Microsoft's collection of multimedia samples written in VB. A nice pile of code that demonstrates common obstacles in multimedia programming.
[>] Multimedia Development under Microsoft's Visual Basic and Borland's Delphi
The purpose of this document is to discuss the relative merits of Visual Basic and Delphi, specifically pertaining to multimedia development under Windows95.
[>] Playing AVI videos using MCI
You can play videos from your Visual Basic application using MCI (Multimedia Control Interface). In fact, it's not that hard once you know the MCI command strings.

Here's an example on how to play an AVI video:

[>] Polar Draw
Polar Draw 2.0 is a powerful ActiveX Control that incorporates diagramming, vector drawing abilities and raster imaging tools, similar to those of MS Visio®, the Adobe Illustrator® or CorelDRAW® software.
[>] Software Creations
A site that's off to a good start. The articles and code library are up and running, and contain some interesting items. A few points have been subtracted due to the very short descriptions of the various items.
[>] VBnet
VBnet focuses mainly on using the Windows API from Visual Basic. The site includes tons and tons of code samples on how to perform any given task using API calls. You must be in serious trouble if you cannot find a solution at VBnet.

As part of VBnet's philosophy, the code isn't contained in downloadable form; rather, it's listed entirely in the article. Inconvenient if there is a lot of code to copy, but more convenient when you want to browse through it to get the general idea.

All in all, VBnet is one of the best code sites around, which is why it deserves the 4 star rating.

[>] VB-World
The maintainers of VB-World do an excellent job in gathering information. Their website contains a lot of exciting and ground breaking source code, most of dealing with the Windows API. There are some book and software reviews here, but it is not this that makes the site worthwhile.

A minor downside is the structuring of the information. The items are divided into categories, but it is not always intuitive where an item might be located; books are stored in Graphics and Multimedia, which I find to be highly counter intuitive.

[>] ZLib Compression Library
A DLL library (with VB code to use it) and an ActiveX control allowing you to compress and decompress using the algorithm from PKZip and gzip.

ZLib compression is also vital to the PNG image format, if you want to read it yourself.