Vista - Where do I get other text-to-speech voices for Vista?

I have 'Microsoft Anna', but I would like to try some other Text-To-Speech
voices compatible with Windows Vista (and thus SAPI 5.3).

Are then any others I can download (preferably for free) from Microsoft
(I've heard of Microsoft Sam' and 'Microsoft Lili' for instance)? If so
where do I find these (e.g., link)? And how does one install a new voice?

Thanx in advance for responses! : )

[==Peter==]

bump, any answers please?

RE: "You can't use Microsoft Sam with Windows Vista due to security holes
in the Microsoft Sam TTS engine."

I assume this is also the reason why Microsoft Mike and Microsoft Mary
will not install on vista. Too bad, Microsoft Mike is the only sapi voice
that I have found to be suitable for high-speed reading. If you are in
Seattle, you can compare Microsoft Anna with the female voice on KHB60 NWS
weather radio to see what I mean. The Anna voice sounds choppy, perhaps due
to word-by-word processing, and a little too emotional with extra clicks and
pops.

In my private work I have found that whole sentence processing is
preferable to word by word processing. The many dynamic text search and
replace operations required for TTS are more efficient working with long
strings because there is less start-up overhead and the processing delays are
more tolerable between sentences than between words.

I have also found that overly high indices of voice emotion or
"enthusiasm" will produce a 'cry-baby' effect similar to the speech of some
spastic-disordered persons. For high-speed reading, it seems to me that Anna
is set rather too close to the threshold for this effect.

For long-term reading, I have found that a low-pitched (85-95 Hz),
radio-announcer style voice is most suitable and soothing. I normally run
Microsoft Mike at the lowest possible pitch setting (as Tex) to achieve this
effect. Perhaps there should be a Microsoft Dave voice in honor of former
Seattle KIXI radio star announcer Dave Ballard.