Performance tip No. 2: Lose the leased lines
Unless you're headquartered in the Sahara, it's time to ditch leased-line Net access. Between Time Warner Business Class, Comcast Business Class, and FiOS, there's bound to be a better, cheaper way to bring high-speed Internet into your environment. A ten-fold Internet bandwidth increase in place of existing T1 circuits is not out of the realm of possibility and can be achieved for a fraction of the cost without compromising reliability.
Granted, T1 and T3 leased lines provide more of a guarantee against latency, but the cost differential is extraordinary, and the maturity of these networks -- especially the business-class products -- has grown substantially. It's time to tell your telco to pull its SmartJacks and bring in something better.
Slow Internet access is always a major complaint among users. Bringing them the same relative speed they get at home goes a long way toward appeasing the masses.
Performance tip No. 3: Let auld acquaintance be forgot
Many businesses cling desperately to elderly application platforms, leaving IT saddled with the high-cost, resource-intensive task of shoehorning old platforms into new infrastructures. This is how you wind up with a brand-new VMware vSphere architecture running a handful of Windows NT4 boxes.
Refusing to let go of the past often results in increased costs, downtime, and fragility of core business systems. Instead of holding meeting after meeting to figure out how to get a 10-year-old accounting package transferred to a new infrastructure, launch it into orbit and migrate to something new. The upfront costs may be more, but they will pale against the long-term costs you'll incur by not severing these ties.
This is a personnel issue as much as it is a technical one. There are always those in IT shops who see everything through the prism of their favored technology, facts be damned. It's not always easy to shepherd these folks through the dark and stormy night of new technology, but remember, hanging on to fixed-purpose IT admins can be as detrimental as hanging on to elderly technology.
Performance tip No. 4: Build a lab