Want to find out how much memory is on your machine, how many processors it has, how fast they are, and that sort of thing?

There's a handy little utility that will tell you all this and more, but it's tucked away in an obscure directory - you might never stumble across it. It's called prtdiag. Run it like this:

/usr/platform/sun4u/sbin/prtdiag -v | more

Here's what the output looks like on my machine:

System Configuration:  Sun Microsystems  sun4u Sun Ultra 60 UPA/PCI (2 X UltraSPARC-II 296MHz)
System clock frequency: 99 MHz
Memory size: 1280 Megabytes

========================= CPUs =========================

                    Run   Ecache   CPU    CPU
Brd  CPU   Module   MHz     MB    Impl.   Mask
---  ---  -------  -----  ------  ------  ----
 0     0     0      296     2.0   US-II    2.0
 0     2     2      296     2.0   US-II    2.0


========================= IO Cards =========================

     Bus   Freq
Brd  Type  MHz   Slot        Name                          Model
---  ----  ----  ----------  ----------------------------  --------------------
 0   PCI    33     On-Board  network-SUNW,hme                                 
 0   PCI    33     On-Board  scsi-glm/disk (block)         Symbios,53C875     
 0   PCI    33     On-Board  scsi-glm/disk (block)         Symbios,53C875     
 0   UPA    99           29  FFB, Double Buffered          SUNW,501-4788      
 0   UPA    99           30  FFB, Double Buffered          SUNW,501-4788      

No failures found in System
===========================

========================= HW Revisions =========================

ASIC Revisions:
---------------
PCI: pci Rev 4
PCI: pci Rev 4
Cheerio: ebus Rev 1

FFB Hardware Configuration:
-----------------------------------
	Board rev: 2
	FBC version: 0x3241906d
	DAC: Brooktree 9070, version 1
	3DRAM: Mitsubishi 130b, version 2

FFB Hardware Configuration:
-----------------------------------
	Board rev: 2
	FBC version: 0x3241906d
	DAC: Brooktree 9070, version 1
	3DRAM: Mitsubishi 130b, version 2

System PROM revisions:
----------------------
  OBP 3.17.0 1998/10/23 11:26   POST 2.0.2 1998/10/19 10:46

So, there you go - as long as you can remember where to find the 'prtdiag' command, you can get a wealth of information about the configuration of your system.