{{{
#!python
class PsycoMiddleware(object):
    """
    This middleware enables the psyco extension module which can massively
    speed up the execution of any Python code.
    """
    def process_request(self, request):
        try:
            import psyco
            psyco.profile()
        except ImportError:
            pass
        return None
}}}

Note that you can use `psyco.full()` instead of `psyco.profile()`. See http://psyco.sourceforge.net/psycoguide/node8.html

'''Note that Psyco should only be used on 32bit systems'''. See http://www.alrond.com/en/2007/jan/25/performance-test-of-6-leading-frameworks .

One possible way to determine the architecture automatically:
{{{
#!python
from platform import architecture

if architecture()[0] != '32bit':
    raise Exception("Don't use this on non-32-bit platforms")

class PsycoMiddleware(object):
    """
    This middleware enables the psyco extension module which can massively
    speed up the execution of any Python code.
    """
    def process_request(self, request):
        try:
            import psyco
            psyco.profile()
        except ImportError:
            pass
        return None
}}}

----

One more issue I have with this -- why is import done on every request as opposed to module load time? The following looks saner to me:
{{{
#!python
from platform import architecture

if architecture()[0] != '32bit':
    raise Exception("Don't use this on non-32-bit platforms")

# let ImportError propagate at module load time so that people can notice and fix it
import psyco

class PsycoMiddleware(object):
    """
    This middleware enables the psyco extension module which can massively
    speed up the execution of any Python code.
    """
    def process_request(self, request):
        psyco.profile()
        return None
}}}

Or even (that's how I use it, and according to `psyco.log()` it seems to work)
{{{
#!python

import psyco
# psyco.log() -- uncomment this if you want to see how psyco performs
psyco.cannotcompile(re.compile)
psyco.profile()

class PsycoMiddleware(object):
    pass
}}}
See http://psyco.sourceforge.net/psycoguide/tutknownbugs.html#tutknownbugs for `cannotcompile()`.

Note about memory consumption:
You can limit the memory that psyco takes to compile code. This can be help full on limited memory systems in conjunction with mod_python apache prefork.
{{{
#!python

psyco.profile(memory=2048) # roughly limit memory consumption to 2048Kb
}}}

See http://psyco.sourceforge.net/psycoguide/node14.html for more information

Known problems:
Psyco is great and you should look into it, but sometimes it can create weird problems (in conjunction with other software) that may be hard to debug. Please remember to turn it off when you have strange / not so obvious problems.