Before I say anything else, let me state one thing. RoseCitySoftware, the developer of Registry First Aid, has a very bad reputation  on WOT. Typically I would never post about freebies from developers that have such feedback about them. However, this particular freebie is through Avanquest, a trusted source of software. I am only posting about this freebie because I trust that Avanquest has made sure the program it not malicious.
That said, like the name implies, Registry First Aid is a registry cleaning program. Here is a description of Registry First Aid, list of benefits, and list of features as per Avanquest:
To get Registry First Aid 7 Platinum for free, follow these simple directions:
Version being given out for free: v7.1.1 Build 1746
Free updates: Unknown
Supported OS: Windows 98 and higher
Update: Apparently this freebie is for 32-bit users only. Thanks everyone who posted below about this!
Download size: 4 MB
Note: Unless specifically stated otherwise in this articlee, Registry First Aid 7 Platinum has not been tested or reviewed by dotTech (aside from checking to make sure this promotion is valid). Please do not take this post as an endorsement/rejection or review of the program. This article is simply to inform about the availability of this program as a freebie. dotTech cannot vouch for the quality (or lack thereof) of Registry First Aid 7 Platinum.
- Visit the promotion page  and fill out the form:
The promotion page is in German (the program will be in English) so if you don’t speak German, here is a rough translation:
If you registered properly you will get a confirmation message, like this one:
- Check the inbox of the e-mail address you registered with. There should be an e-mail from email@example.com with the subject of Ihre Registry First Aid Seriennummer: E-Mail-Bestätigung?. In the e-mail there will be a link you need to follow to confirm your registration:
Click on the link or copy + paste in your browser URL bar.
- Once you visit the link, the webpage that opens will display your registration key:
Copy the registration code because you will need it soon.
- Download  and install Registry First Aid 7 Platinum.
- After installation run Registry First Aid 7 Platinum and register it by going to Help Menu -> Enter Registration Key:
You have to enter the registration code you got in the Serial number box, but you can enter whatever you want in the User name box.
If you have trouble getting Registry First Aid 7 Platinum for free, post below and other dotTechies and I will try to help.