Currently, there are a few good tools available that will be presented here and on the blog.
DNSCheck
With this tool, which is being developed by .SE, you can easily check several elements of a DNS zone. The project is open source and available here. For a quick start and first impression, check out the demo.
DNSSEC Validator Firefox Add-On
This add-on for firefox is being developed by CZ NIC. We have blogged about it here.
SecSpider
SecSpider is a project which polls domains from various vantage points worldwide gathering DNSSEC information. It gives a detailed view of the paramters used to sign the domain and reports potential problems. You can see the report it generates for our domain as an example. If you want to include your domain you can submit it free of charge on their homepage (Note: It takes several days for the first results to show up).
DNSViz
DNSViz provides a graphical representation of a domain delegation. It also shows extensive information about the DNSSEC keys used in a specific delegation and the status of them. You can see the result for our domain as an example.