Simple, clean example of PHP, MySQL shopping cart scripts

Ok, while am pretty sure could do this myself from scratch without any real issues, just wondering what guys would recommend looking into/at with regard to something like examples of relatively simple, clean, free shopping cart script examples, preferably making use of/including the following (unrelated) features etc.:-

php
mysql
admin section for products/orders
product detail possibly including title, pricing, keywords, categories, descriptions, and possible image uploads
front-end user registration
shopping cart support
order placement/checkout
etc. etc.

Like said would like something relatively clean, simple, etc. since could then easily enough make mods/changes to it if/when wanted to add other features to it, or turn off existing ones, but anyway...suggestions?

Have already had a look at a couple of ones out there, but they generally seem to try to implement too many extra features that don't seem necessary as such, etc.

Jacob Kruger
Blind Biker
Skype: BlindZA
'...fate had broken his body, but not his spirit...'