Not sure that DOI is up to sound files, but here are a couple of radio ads which DfES is running to push Educational Maintenance Allowances.
The Directgov people are very excited about them because they are the first campaign to use directgov.gov.uk/campaign_name as the response URL rather than anything departmental or campaign specific. I thought it might be more notable that the ads only offer an online response route – can’t quite imagine our doing that for a while yet.