IPAM and you.. tell me your stories

IP Address Management appears to be something that came and went from CIO buzzword bingo.. but i'm not convinced the problem is completely solved (or addressed) in many enterprises, so I am keen to hear what people are doing or what they have seen in regards to IPAM in environments they manage.

So I thought I would put together some questions to spark the discussion, especially if you are using Red Hat in your IPAM solution. Also interested to know generally what people are using for IP allocation, particularly on their Red Hat server fleet.

I am expecting answers such as (with more detail):
- We use DHCP and cross our fingers
- We use DHCP with manually configured reservations
- We ping IPs in the subnet until an address fails to respond (Bingo!)
- We email the network guys and they send back a spare IP
- We have an elaborate Excel spreadsheet/wiki page
- We use an IPAM product/appliance but allocation is a manual process
- We use an IPAM product/appliance and allocation, DHCP, DNS etc. is all automated and host register through an API on build
- We use a bespoke / in house application

Further to this...
do you use DHCP for server IP allocation?
do you use the same IPAM solution for both servers and desktops?
do you only use your IPAM solution for 'cloud' or 'cattle' segments of your network?
do you use/can you recommend an opensource product you have had success with? (eg. http://phpipam.net/)
can you recommend a commercial product (is that allowed here?)

Lastly...
Are you happy with the solution you're using?
If you were to implement it (again).. how would you change your approach/solution?

WWRHD? Does Red Hat have a mature solution that I have missed completely?

Cheers!