[Typo3] link indexing

[Raymond Irwin]

hi list,

i want to implement a link indexing site. something like yahoo or dmoz 
with a range of functions like:

• Premium and Normal Links
• Ranked By Highest Clicks In, Title, etc.
• Special Listing Menu
• Search For Links
• View Link Details
• Image File for Premium Link
• Write A Review
• Add To Favourite
• Suggest To A Friend
• Link's Rating
• Submit A Site and Approval
• Add, Edit or Delete Link
• Link Category and Details
• Image File for Premium Link
• Check Broken Link
• Check Reciprocal Link
• Select Link Category To Check
• Add, Edit or Suggest Link Category and Details
• Allocate Parent Category
• List All Categories
• Edit or Delete Category

etc...

i've been working with typo3 for some time but haven't seen anything of 
this sort in the extension repository. i would like to know if there is 
anyone who has done such a thing with typo3 or could give an educated 
guess on the amount of energy (money / time) one would have to spend on 
programming an extension to do this. if there are other known systems 
that will support a range of features in this way, i would also be happy 
if you'd share your experience.

greetings, raymond