Barbra Streisand: is she worth it? Photograph: Kevork Djansezian/AP
£500.
That's a plane ticket to the far east. Half a month's rent for a one-bedroom flat in central London. A Starbucks latte every day for the best part of a year.
Or two hours in the company of Barbra Streisand.
Disturbingly, I've already been making the calculations in my head. I'm not planning a trip to the far east. I don't like latte. Just think how much money I've saved already. I draw the line at questioning whether I really need a roof over my head, but only just.
What I haven't questioned is whether a ticket to see Barbra Streisand in concert later this year might actually be worth £500.
It's not as if she's even that good. She's 65 now, and the voice isn't what it used to be. A lot of her songs are quite dirge-like. And she spends far too much time engaging in poorly scripted banter.
Her people (of course she has people. People who need people are the luckiest people in the world) claim that FA cup-final tickets go for £1,600, so £500 is practically giving them away. (I tried this argument on a friend. "Yeah," he snapped. "But you get a fucking executive box with fucking free booze. What does she give you? A free programme?")
And, they add, the concert will be an event. Seeing Babs perform is like witnessing Elvis, or having tickets to Frank Sinatra's interminable farewell.
But the real attraction isn't the famousness of the star, or the tell-the-grandchildren factor. Nope. The real appeal is more akin to the freak-show traditions of a bygone age: we want to gawp at the colossal size to which the human ego can swell.
Surrounded by 23,000 of her closest friends Babs will, undoubtedly, muse on the state of world affairs. Why weren't voters persuaded by the benefit concert she gave for the Democrats? Is she a target for international terrorism?
Duetting with dead crooners has now become commonplace, but Streisand goes one better: she duets with a two-storey projection of herself in Yentl, the film that - she never fails to point out - she wrote, directed, produced, and starred in. At her last concert, a 12-year-old girl, representing the pubescent Streisand, joined in as well, the audience worshipping before a holy trinity of Babs.
How do I know this? Because I bought the DVD. The ego is there, in my living room, for £13.99.
On the other hand, if Streisand releases 35 more DVDs, and I don't buy any of them, that would justify the price of a concert ticket. And I'd still be able to afford the rent.