Wildcards in a Windows hosts file

To answer your question, you cannot use wildcards in the hosts file under Windows.

However, if you want to only change the hosts file to make new sites work.... you can configure your Apache like this and you don't have to keep editing it's config:

http://postpostmodern.com/instructional/a-smarter-mamp/

Basically a quick summary based on my setup, add the following to your apache.conf file:

 LoadModule vhost_alias_module modules/mod_vhost_alias.so

 NameVirtualHost *:80

  <Directory "/xampp/sites">
      Options Indexes FollowSymLinks Includes ExecCGI
      AllowOverride All
      Order allow,deny
      Allow from all 
  </Directory>

  <VirtualHost *:80>
      VirtualDocumentRoot c:/xampp/sites/%-1/%-2+/
  </VirtualHost>

This allows me to add an entry like:

127.0.0.1       test.dev

and then make the directory, c:\xampp\sites\dev\test and place the necessary files in there and it just works.

The other option is to use <Directory> tags in apache.conf and reference the pages from http://localhost/project/.

I don't think that it is possible.

You anyway have to modify the apache virtualroot entries every time you add a new site and location, so it's not a big work to syncronise the new name to the Windows vhost file.

Update: please check the next answer and the comments on this answer. This answer is 6 years old and not correct anymore.

Acrylic DNS Proxy (free, open source) does the job. It creates a proxy DNS server (on your own computer) with its own hosts file. The hosts file accepts wildcards.

Download from the offical website

http://mayakron.altervista.org/support/browse.php?path=Acrylic&name=Home

Configuring Acrylic DNS Proxy

To configure Acrylic DNS Proxy, install it from the above link then go to:

1. Start
2. Programs
3. Acrylic DNS Proxy
4. Config
5. Edit Custom Hosts File (AcrylicHosts.txt)

Add the folowing lines on the end of the file:

127.0.0.1   *.localhost
127.0.0.1   *.local
127.0.0.1   *.lc

Restart the Acrylic DNS Proxy service:

1. Start
2. Programs
3. Acrilic DNS Proxy
4. Config
5. Restart Acrylic Service

You will also need to adjust your DNS setting in you network interface settings:

1. Start
2. Control Panel
3. Network and Internet
4. Network Connections
5. Local Area Connection Properties
6. TCP/IPv4

Set "Use the following DNS server address":

Preferred DNS Server: 127.0.0.1

If you then combine this answer with jeremyasnyder's answer (using VirtualDocumentRoot) you can then automatically setup domains/virtual hosts by simply creating a directory.