Sever & Client side programming challenges

Hi all,

Bit of an ambiguous post this one and im not quite sure that this fits into any particular category really, so if the mod feels it should be elsewhere then feel free to move this post!

Basically I want to improve my web development skills with PHP & MySQL (intermediate) ASP.Net & MsSQL (Total Beginner) and AJAX (Total Beginner), so obviously I need to practice and experiment, the trouble is that I can never think of any decent problems to solve or cool little programs to write that will help me improve my skills but that could be done in the evenings and accomplished within a couple of weeks (i.e. not a full blown e-commerce site with shopping cart and inventory management).
I have a fairly decent understanding of programming concepts, so I am looking for ideas that will get me familiar with the syntax and any built in functions of languages rather than ideas to get me familiar with programming concepts.

What I would like people to suggest.

• Little projects that you think would be useful for a learning experience or from an end user perspective (always useful to put in a portfolio). For example I had the idea of a password generator where the user can select the length of the password and whether it contains numbers and letters, or just numbers etc.
• Projects or bits of work you have done and found that you learnt a lot through doing.

I understand that this is a bit of a random question but I would appreciate your input.

Cheers

Well if you are interested in learning PHP & MySQL perhaps start with a simple contacts or address book. That's how I cam to understand how each works.