I disagree with Nick

So Clegg thinks that a minority government would be unable to survive until Christmas.  The BBC reports:

The UK could be poised for a second general election by Christmas if either Labour or the Conservatives try to form a minority government after 7 May, Lib Dem leader Nick Clegg has warned.

He argued that only another "stable and strong" coalition involving his party could save the country from a re-run.

I would suggest that he is under-estimating the difficulty in actually triggering a general election in such circumstances.  According to the Fixed-term Parliaments Act, there are only two ways to call a general election outside of the usual five year term.  First, the House of Commons votes by a two-thirds majority for there to be such an election; or, second, the House of Commons passes a motion of no confidence in the Government, and an alternative government cannot be established within two weeks thereafter.

Given the expected parliamentary arithmetic after Thursday, where neither the Conservatives nor Labour have an overall majority, it seems to me that the Conservatives and Labour would actually have to agree that neither of them should continue as a minority government before they could call a general election.  That is of course possible but seems improbable in the short term.

I don't see why a minority government of one colour or another should not limp along indefinitely.