Additionally the performance increase is important, but doesn't matter for everything network related.
In other words I'd say it's almost worth what you pay for it.
It's easily the most noticeable upgrade I've ever done.
If you buy a sony or apple laptop, replace the drive yourself. I just bought a 13" MBP and bought a $25 caddy to put my Vertex 2 in the DVD bay. That way I have Windows 7 booting from that SSD, OSX on the normal HDD with extra storage available there. Of course you could just replace the HDD with an SSD and not void your warranty.
The only real problem with that solution is that 128gb isn't enough for some people, but it is not difficult to offload the data to another storage device, either internally or externally. I've been keeping under 128gb on my main laptops (MacBook Pro and Air) for a year and a half now (when I first switched over to using SSDs) without a problem.
But you can always have more than 1 hard drive. Buy a 500gig one for all your large file content and use the smaller one for the OS. Pretty much all SSDs come in laptop drive format so I don't know where this $800 number is coming from. They might have been $800 last year, but transistor prices drop pretty fast.
I have 2 drives in my macbook pro -- 120gig vertex 2 ssd, and a 500gig samsung "old style" hard drive.
$200 for an SSD is a far better use of money for the average programmer than say the upgrade from I5 to I7 on a 13" MBP. There are many parts of your computer which you'd spend $200 on that get you less of a general every day performance boost than a SSD.
The reality is that it significantly increases performances for all workloads but streaming videos (huge sequential reads).
Most of computer usage is random access to small files, and that's a field where SSDs utterly annihilate rotating platters (not that rotas have any advantage but storage capacity, mind you, SSDs are also superior in seq read and write, but on random we're talking 2MB/s on 4k random write for a VelociRaptor to >200MB/s for a Vertex 3; 0.68MB 4k random read for a VR to >90MB for a Vertex 3, for sequential performances the difference will be a factor of 2 or 3 tops between a VR and a top-of-the-line SSD)
The difference is, of course, even more impressive for laptop drives: most laptops don't house 10k, 10W monsters like the VRs
A fast CPU is worthless if you're burning 30% of your cycles waiting for the HDD to deliver your data. Relying on file cache is not good enough.
Just to give a rough idea - 4k random writes:
Vertex 3 - 214 MB/s
WD VelociRaptor - 1.9 MB/s
Textmate is another excellent example. Search in project is completely usable with an SSD. I had temporarily switched to AckMate because of how unbearably this feature was, now it's instant again.
Booting faster is the least of my cares as my laptop is only rebooted when updates force me to.
Those of us with one know that really isn't the case, but of course it's hard to convince someone to spend that much money on something they don't think will make a difference.
Since I put one in my late-2008 MBP at Christmas, I've not seen a single beach ball. Best upgrade ever.
Either that, or a case of blub.
SSDs are one of those pieces of hardware closest to magic you can find, the differences between HDD and (modern) SSD are so big it's hard to understand them until you've experienced them. I know I didn't before I got mine, but Anand's writing on the subject convinced me there was something to it (anand being a person whose opinion I respect greatly, and one of those who dived early into understanding SSDs, he didn't hesitate crucifying early crappy SSD, and his SSD series are fantastic in their breadth and depth)
Then the Crucial RealSSD C300 (256 GB) went on sale prior to xmas 2010, and my girlfriend ordered one for me surreptitiously, after overhearing conversations between me and a friend about SSD performance.
As it turns out, I was completely wrong to be skeptical. The differences should have been crystal clear to me. Think of the difference between using your iPhone/iPad/Android and your computer. Notice how everything on your phone occurs nearly instantly. Most of us don't even consider it, because these devices never came with slow magnetic platter drives. Even with minimal (by desktop standards) RAM and absolutely anemic CPU power, these devices manage a level of responsiveness that makes them disappear in to the background as we use the software. An SSD brings this experience to your desktop. The performance difference is present in everything that you do, not just launching applications.
What a horrible argument.
You won't see a hybrid able to saturate a 6Gbps SATA connection on random-access any time soon.
First, a lot of people are talking about using two drives. On Windows this model does not work. Moving programs from C: to D: will often screw up registry settings and other crap like that. On OSX and Linux, thanks to a single root filesystem and symlinks, this model might work better. Furthermore, I have to manage moving files back and forth. This is a problem algorithms should take care of and no OS does this yet.
Secondly, a lot of people are saying the Momentus benchmarks are terrible. This seems obvious. Any standard benchmark does not take advantage of a large read cache. You have to use some sector of data over and over again in order for the drive's algorithms to put it into the SSD cache. Read real world benchmarks here: http://www.anandtech.com/show/3734/seagates-momentus-xt-revi...
I have a 3 year old Thinkpad T61p with a still decent Core 2 Duo and 4 GB of ram. After three years it felt kind of slow so I had two options: 1) Buy a SSD for 250 Euro or 2) buy a completely new laptop for > 1000 Euro.
I went the first route and after working with the SSD for half a year I'm pretty sure that an expensive new laptop with a traditional hard drive would not have resulted in such a tremendous speedup as the SSD did.
So please don't think of the 200$ for an SSD as "these 200$ will buy me a new hard drive" but instead think of this investment as "these 200$ will buy me an awesome new computer".
For my desktop I have gone for the Highpoint Rocketraid 1220. it's a two port SATA III <£50. Add a HDD of your choice and an SSD and you have your own hybrid logical disk. I am testing with a 500gb caviar black and an old OCZ Vertex 30gb.... Arrives today!
It also only uses the cache for reads, and not writes. Writes is where the magic happens! If I wanted more read cache I'd just get more system RAM.