external hard drive

Hi,
I need some suggestions from people who are familiar with "external hard drives".

Shortly, I am looking for one which is:

1) small in size (easy to carry)
2) 40GB is more than enough for me ( so even 20GB would do it)
3) has the ability to work without the power cord(no battery needed)
4) around $150
5) reasonable transfer rate
6) USB2.0

Which brands/models would you suggest?

Freecom FHD-2 pro is something that I liked, but $199 is a bit expensive. All I need is one which I could use to take my files from home to work and vice versa.

I am not very familiar with the external hard drive technology, so please feel free to comment about anything releated(e.g. my priority list).

Any suggestions will be much appreciated.
Thanks.

Nobody has any suggestions?

As with most purchasing questions, I recommend checking out newegg.com and other major online computer suppliers. You can look under "external harddrives" specifically, see what is available and for how much, what features they have, and even see reviews from other buyers.
As for your priorities, they are yours. None of them are impossible to achieve, though you might need to prioritize them. For example:http://www.thinkgeek.com/computing/drives/5ad4/ seems to fit your needs perfectly, but its $20 more than you wanted to spend.

karsh44,
Thanks for the information and your suggestions.