I wrote yesterday that I was unconvinced by the Microsoft-Nokia (Mokia? Nokrosoft?) alliance. Both companies have smart people, vast resources and similar aims, but whenever firms talk about collaborating, shared development and the like, warning lights are illuminated. All too often, the real collaboration stops at the press release and the only real shared vision is an agreement to pose in front of analysts, media and customers, shaking hands and talking about synergies in the hope of a lift in perception and stock price.

The hard business of sharing development is much more scarce than ink spilled over such agreeements and for every real alliance that has paid dividends there are a dozen that have petered out. Sun-Oracle (before Larry Ellison worked out, Victor Kiam-like, he liked Sun so much be bought the company) and Intel-Microsoft's Wintel duopoly have been formidable axis powers but these are exceptional. Here's a list of five others that went south.

5. Sun-Netscape. Sun made a big deal about this tie-up, established just after AOL bought Netscape in 1999 and designed to capitalise on the fact that a lot of Netscape server software was ending up ino Sparc servers. To this day, Sun is still struggling to come up with a convincing software business and the Web 2.0 generation asks 'what's Netscape?'.

4. Sun-Google. Thinking about it, Sun has been involved in a lot of damp squibs over the years and despite rumours of something rather significant, this 2005 agreement turned out to be as interesting as a wash-out in the third day of a meaningless county cricket match. As the hapless Forbes reporter was forced to conclude: "The broad consensus is that the deal announced between Sun and Google will have little or no impact on Sun in the near- or mid-term, and little impact on Microsoft. Further, many Wall Street analysts agree that the long-term financial benefit to Sun from the software collaboration is questionable." That'll be what the Americans call a yawner then.

3. The ACE Consortium. The boot was on the other foot in 1992 when a gang of IT vendors teamed up to steal Sun's workstation thunder. Compaq, Silicon Graphics, Microsoft, SCO and Digital were among those planning to build a platform based on MIPS or Intel processors. Things fell apart faster than a marriage featured on the cover of OK magazine.

2. AIM. With both firms ailing at the start oif the 1990s, a pact between IBM and Apple, in asssociation with Motorola, led many to suggest that this would be the precursor to a merger. The combination did lead to the development of the PowerPC processor that was used for years in Macs but never summoned the futuristic operating environment and development platform that was envisaged with the creation of Taligent and Kaleida Labs.

1. Pandesic. This dead, unlamented combination was an e-commerce effort of 1997 that jogged along for a while the expired a few years later have consumed vast sums from the Gargantua and Pantagruel of Chips and ERPs. SAP repeated the trick later with Commerce One. Commerce One was a white-hot online marketplace maker deemed revolutionary by pundits and SAP's financial and strategic support gave it plenty of heft but by 2004, Commerce One was in Chapter 11. SAP had effectively jumped ship a couple of years earlier by ending a licensing agreement. So much for the revolution.