Maybe you can find any and all the replacements of a Windows application on Linux, but there is a way through which you can run your favorite Windows application on your Linux operating system. Now I recommend you 6 free tools which will help you run windows softwares on Linux System. And help you to run virtual PC on any OS.
1. Â Wine HQ
Wine lets you run Windows software on other operating systems. With Wine, you can install and run these applications just like you would in Windows.Wine is still under active development. Not every program works yet, however there are already several million people using Wine to run their software.
Open Source and User Driven
Wine will always be free software. Approximately half of Wine’s source code is written by volunteers. The rest is sponsored by commercial interests, especially Codeweavers who sell a supported version of Wine.
Wine is heavily reliant on its user community. User tests fill our Application Database to track how well programs work, and all the answers in the forums come from volunteers.
2.  VirtualBox
VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers, it is also the only professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL). See “About VirtualBox” for an introduction.
Presently, VirtualBox runs on Windows, Linux, Macintosh and OpenSolaris hosts and supports a large number of guest operating systems including but not limited to Windows (NT 4.0, 2000, XP, Server 2003, Vista, Windows 7), DOS/Windows 3.x, Linux (2.4 and 2.6), Solaris and OpenSolaris, and OpenBSD.
VirtualBox is being actively developed with frequent releases and has an ever growing list of features, supported guest operating systems and platforms it runs on. VirtualBox is a community effort backed by a dedicated company: everyone is encouraged to contribute while Oracle ensures the product always meets professional quality criteria.
3.  Qemu
QEMU is a generic and open source machine emulator and virtualizer.
When used as a machine emulator, QEMU can run OSes and programs made for one machine (e.g. an ARM board) on a different machine (e.g. your own PC). By using dynamic translation, it achieves very good performance.
When used as a virtualizer, QEMU achieves near native performances by executing the guest code directly on the host CPU. QEMU supports virtualization when executing under the Xen hypervisor or using the KVM kernel module in Linux. When using KVM, QEMU can virtualize x86, server and embedded PowerPC, and S390 guests.
4. Bochs
Bochs is a highly portable open source IA-32 (x86) PC emulator written in C++, that runs on most popular platforms. It includes emulation of the Intel x86 CPU, common I/O devices, and a custom BIOS. Currently, Bochs can be compiled to emulate a 386, 486, Pentium/PentiumII/PentiumIII/Pentium4 or x86-64 CPU including optional MMX, SSEx and 3DNow! instructions.
Bochs is capable of running most Operating Systems inside the emulation including Linux, DOS, Windows® 95/98 and Windows® NT/2000/XP or Windows Vista. Bochs was written by Kevin Lawton and is currently maintained by this project.
Bochs can be compiled and used in a variety of modes, some which are still in development. The ‘typical’ use of bochs is to provide complete x86 PC emulation, including the x86 processor, hardware devices, and memory. This allows you to run OS’s and software within the emulator on your workstation, much like you have a machine inside of a machine. For instance, let’s say your workstation is a Unix/X11 workstation, but you want to run Win’95 applications. Bochs will allow you to run Win 95 and associated software on your Unix/X11 workstation, displaying a window on your workstation, simulating a monitor on a PC.
5. rdesktop
rdesktop is a free, open source client for Microsoft’s proprietary RDP protocol. It is released under the GNU General Public License and is available on Unix-like systems such as BSD and Linux. Supported servers include Windows 2000 Server, Windows Server 2003, Windows Server 2008, Windows XP, Windows Vista and Windows NT Server 4.0. Rdesktop currently runs on most UNIX based platforms with the X Window System, and other ports should be fairly straightforward.
6. Xen
The Xen® hypervisor, the powerful open source industry standard for virtualization, offers a powerful, efficient, and secure feature set for virtualization of x86, x86_64, IA64, PowerPC, and other CPU architectures. It supports a wide range of guest operating systems including Windows®, Linux®, Solaris®, and various versions of the BSD operating systems. The Xen hypervisor is a unique open source technology, developed collaboratively by the Xen community and engineers at over 20 of the most innovative data center solution vendors, including AMD, Cisco, Dell, HP, IBM, Intel, Mellanox, Network Appliance, Novell, Red Hat, SGI, Sun, Unisys, Veritas, Voltaire, and Citrix. Xen is licensed under the GNU General Public License (GPL2) and is available at no charge in both source and object format. Xen is, and always will be, open sourced, uniting the industry and the Xen ecosystem to speed the adoption of virtualization in the enterprise.
