£1k per day (especially if the full 24hrs) is not massively OTT in my experience. There are plenty pf consultants out there pulling in anywhere between £700-£1500 for their services (IT, Project Management, Security, etc...).
The trick about contract rates is making your employment seamless and then you're into mega-wonga; sadly for most, it is 1 week here, 2 weeks there, a month here and a month there, intersperced with 1-2 weeks between contracts...
LJ